Surfing Troves

WinEdit: Cannot Jump from PDF to LaTex source?

2014-08-08T17:25:00.001-07:00

You may have already known about the convenient feature of WinEdit LaTex environment that allows you to jump from the generated PDF line, when clicking that line, back to the corresponding tex source line in the WinEdit editor window. This is immensely helpful and conducive to efficient Tex editing and revising.

However, somehow you may find that the feature suddenly fails to work. That happens to me recently, making a lot of headaches when fiddling with how to fix it and bring the nice feature back to work.

Regardless of how other online posts complicated this solution, here is the quick steps:

1. Download Sumatra PDF reader and install it (to avoid unnecessary trouble, just install it to the default folder, for instance 'C:\Program Files (x86)").

2. Open your WinEdit and get into 'Options' (from the main menu) -> 'Execution Modes'

3. In 'PDF Viewer' tab, set Sumatra PDF reader (the executable SumatraPDF.exe) as the 'PDF Viewer Executable'; leave 'Use --synctex switch when --src is enabled' unchecked; fill '--synctex=1' in SyncTex switch box

4. Move to the 'Console Applications' tab, choose 'PDFTexify' in the navigation menu on the left-hand side, fill '--pdf --tex-option=--synctex=-1' in the 'Switches' box.

5. Ctrl+Shift+'P' (or choose 'PDFTexify' from the 'Tex'->'PDF' menu items) to build your PDF; save settings and get back to your editing environment.

6. Now try to double click a line in the PDF, the beautiful functionality should play like a charm!

Solve PDF font-embedding really quick

2014-08-08T15:04:00.001-07:00

To make your PDF files easy to view by others who may have a different font environment from where you generated the PDFs, you are usually in want of embedding all fonts in the files. In fact, many of the professional publishing agencies, such as the Conference Publishing System (CPS) of IEEE or ACM, have set mandatory requirements in that regard on the paper authors preparing the camera-ready versions.

This is the most straightforward recipe:

1. Open you problematic PDF in any application that provides a capability of printing (such as Acrobat Reader or Acrobat Pro).

2. Go to 'print' page and choose 'Acrobat PDF' as the printer.

3. Get into "properties" of the printer.

4. In the 'Adobe PDF Setting' tab, get into 'edit' next to the 'Default Settings' item.

5. Get into 'Fonts' from the navigation menu.

6. Choose the 'Embed all fonts' checkbox.

7. Select 'All' items in the 'Never Embed' listbox and Remove all of them.

8. Save the settings (a new setting will be created which can be used next time upon the same need) and go back to the 'print' page.

9. Print your PDF into another PDF, where all fonts are now embedded.

10. Problem should be solved already.

* To check if all fonts have been embedded:

In Acrobat Reader/Pro, go to 'properties' from the 'File' menu, look into the 'Font' tab,

for each successfully embedded font, there should be something like '(Embedded subset)'.

Passing reference by value in Java

2014-04-04T13:36:00.006-07:00

Having been sticking to C/C++ for a decade, I know relatively clearly about the notion of "passing by value" and "passing by reference/address", and the memory models behind them. Embarrassingly, however, it is just a recent clarification that "passing reference by value", a freak concept in Java, is not only in essence unequivocally different from the preceding two, but really closely related to them. Most important, this nuance in name but connections underneath is what has been confusing me for all times I was intensively programming in Java for the past two years.

Without re-spinning the explanation, I just simply summarize toward the gist about this topic, using the information in courtesy of Dale King, by posting the core question and the thorough answer to it.

Does Java pass objects by reference or by value?

The answer is NO! (that is, Java neither passes objects by reference nor does that by value!)

The fact is that Java has no facility whatsoever to pass an object to any function, and the reason is that Java has no variables that contain objects.

It is common to confound the concept of an object reference variable with that of an object instance, but all object instances in Java are allocated on the heap and can only be accessed through object references.

So if I have the following assignment:

String g = new String( "Hello" );

The variable g does not contain the string "Hello", it contains a reference (or pointer) to an object instance that contains the string "Hello".

Java only has variables that hold primitives or object references. Both are passed by value. Now, it comes naturally that Java does pass (object's) reference by value. if the parameter being passes is an object (rather than a primitive type of value).

Building and Extending VirtualBox Source Code in Fedora Linux

2012-11-26T20:47:00.001-08:00

The following practice was done in Fedora 17 Linux on an AMD-64 arch. If you are playing around VirtualBox in Ubuntu, you may find it much easier than the following talks about.

Of course, the reason why you wanted to build the source package of the Virtualbox instead of downloading the executable by automatical installation provided by such and such an "installer" is very likely to be your desire to extend or develop on the current VirtualBox distribution. I was doing this for extending it to include a performance monitor for the VMM at the core.

Now go ahead building the source package in the first place. No exhaustive details, just critical steps to work around traps and annoying errors you might have got stuck on, since I have no intent to write tutorial for building VirtualBox in Linux given the existing tutorial maintained on the official site of the developers of VirtualBox. See "Linux build instructions" in there.

1. failure in getting through the first-step "./configure". Here are the cures:

for openWatCom, if you can not build from the source code successfully within at most 20 minutes, forget about that daunting way of doing it. Instead, just install it using the installer found here to save yourself!
for "LIBIDL"'s missing, sudo yum -y install LIBIDL-pluginbase-devel (the name might not be exactly as this, correct it as needed)
for Qt4, compiling the source code rather than just installing the executables to install. Using the opensource-everywhere source package (found here) is recommended.
* this may take long, be patient and after it is finished, add the directory holding the "qmake" executable to the environment variable "PATH" and make it take effect before doing "./configure" again.
for PulseAudio, use the disable flag corresponding to it as an option to the "./configure" launch.
upon failure to find "lstdc++", "whereis libstdc++.a" and then copy it from where you found it to the standard place "/usr/lib64"
For missing headers for "32-bit support", using "--nonfatal" option provided with the "./configure" itself. By doing this, we simply ignore, and hence sacrifice, the support of 32-bit additions by the VirtualBox
* For other errors, put it into the comment area of this post. I will try to help with them.

2. failure in getting through the "make" step (actually "kmk" instead of "make", a KBuild variant of the GNU make). Here are the other cures:

for the repulsive error like "spec failure: g++: invalid/unrecognized option "-m"", do "kmk -ik" anyway but keeping the error log by appending " 2>errors 1>&2" to it
grep "g++: " errors > makeup.sh and then replace all "g++" with "g++34" (under Fedora 17, g++34 is installed by default and otherwise I presume you have it by any means. Or I am not sure for now how to get this hurdled bypassed).
do the brute-force "complete" compilation by "kmk -bBik all"
And, now run "sh makeup.sh". If things are done, you should be able to locate the "VirtualBox" executable under the $installDir/linux.x86/release/bin directory, run it and enjoy your success.
Otherwise, you will need go back to the "errors" file to find other failures in issues other than the "invalid -m options with g++", for example some compilation errors in your own hacking code.

3. finally, failure in launching the newly built Virtualbox frontend (the backend, VBoxSVC and XCOM service will automatically be boosted up when the first frontend gets started). Here are the final cures:

for messages complaining about "can not load vbox driver" or something like that when you are trying to start a virtual machine, get back to your terminal and do "sudo modprobe vboxdrv". If this does not do the trick, using insmod directly by "sudo insmod $path/vboxdrv" where "$path" indicates where the vboxdrv.ko file is located. You can get the path by "find -name" or "locate" followed by "vboxdrv.ko"; Alternatively, you can simply do "sudo kmk load" under the top source code directory to get this step done as well.
for complaints like "driver is not accesible", which may pop up at the time of starting a VM too, do "sudo chmod a+rwx /dev/vboxdrv" - by default, the vbox driver should have been placed in /dev/

Brother HL-2270DW Laser Printer (Google Affiliate Ad)

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Hacking Bluetooth Modules in Fedora 17 Linux

2012-11-26T09:41:00.001-08:00

Having figured out how to successfully build the original source package of the Bluetooth modules downloaded online (see my older post on how to build), now we can head to hack those modules in order to customize certain Bluetooth functionalities on demand (as is actually, at least one of many others, the reason why we wanted to build the source package instead of downloading the executable in the first place).

To hack the Bluetooth modules and make it really effect for ordinary users, we need both categories of module - the kernel module and the user module. While the tricks required to build the kernel modules ca be found in the older post on how to build, building the latter on the same platform (AMD64, Fedora 17 Linux) has been straightforward at least for myself(your report of troubles in building the user space modules of Bluetooth, i.e. as downloaded from bluez.org, is welcome to be put into the comments of this post). Remember, however, as was somehow seemingly required, you need to "sudo" the execution of the common sequence of "./configure" -> "make" -> "make install" if you are not logged in as the root directly.

Now following things to be followed, no big deal, just the below listed,

1. Having successfully built the kernel modules should have given you a group of module binaries (.ko files) that has been moved ("installed") to the directory of "/lib/modules/`uname -r`/updates" by default, where subdirectories include the following together with example, but not all, enclosed files :
driver[/btusb.ko], net[/bluetooth/{rfcomm.ko, bnep.ko}], and net/[bluetooth.ko].

* if you have not yet successfully got these files, you have not yet successfully built the kernel module then. Check again you have really followed and went through successfully the following steps before getting back again to the older post on how to build:
under the top source directory, do
"make clean" -> "scripts/selectdriver bt" -> "make install-modules"

2. before you can "mount" the newly built kernel module for bluetooth above, make sure you "dismount" the currently mounted one as the system has done while booting the kernel by default. Do these:
"killall -9 bluetoothd" -> "sudo modprobe -r bnep" -> "sudo modprobe -r rfcomm" -> "sudo modprobe -r btusb" -> "sudo modprobe -r bluetooth". An alternative to "modprobe -r" could be "rmmod".

* note if the bluetoothd (see below for more about it) is still running, you will get "cannot remove module xxx, xxx is busy/in use" when you are doing the aforementioned "dismounting" steps.

* note that the btusb.ko module is directly associated with the "bluetooth icon" on the toolbar of the desktop , which is presented there by default. So when you killed this module, that icon disappeared. In return, you can use the disappearance of that icon as a simple flag that this module has been removed successfully.

* If you still had trouble removing them, play the trump now:
"sudo init 3" -> "log in a root" -> "do the same series of modprobe -r"

3. Having successfully built the user space module should have given you a set of binary executables and objects (lib files) besides documentation related files to the directory you have indicated when doing "./configure" before. Check the installation directory for such subdirectories as that includes the following together with example, but not all, enclosed files :
bin[/hcitools], sbin[/bluetoothd], ....

Here we actually are concerned about the bluetooth daemon server bluetoothd only, as is to be running in the user space to bridge the bluetooth applications and the underlying bluetooth kernel modules.

4. Now start mounting your own hacked modules and make them effect by following steps:

"sudo mv /sbin/bluetoothd /sbin/bluetoothd.org" (just back up the original one in any way you prefer)
"sudo cp $installDir/sbin/bluetoothd /sbin/" (this is critical, directly running this daemon from the $installDir", at least when the "installDir" is not the one taken as default, has fallen to failure for me)
"sudo /sbin/bluetoothd [-n] [-d]"
"sudo modprobe bluetooth,bnep,rfcomm,btusb"

Now you should have been working with your hacked bluetooth modules.

* using "-n" to run bluetoothd in a non-daemon will show you the running log that can give you a sense of how the user modules get loaded and run; further, the addition of "-d" to the command line can provide you even more details of the internal dynamics of the user space code.

* "dmesg -T | grep "bluetooth" can give you running logs of the kernel module, about their being loaded and run.

Enjoy hacking!

Nikon D5100 16.2MP Digital SLR Camera with AF-S DX Nikkor 18-55mm f/3. (Google Affiliate Ad)

Build Bluetooth Kernel Module in Fedora Linux

2012-11-19T18:32:00.003-08:00

Prelude:
If you do not encounter issues like one of the following, you are free to leave now so as to avoid a waster of time reading more below.

Download Linux Bluetooth kernel module source code

Can not compile Linux Bluetooth kernel module

/sbin/modprobe: invalid option -- 'l'

========================== Start =====================================

Although this practice was with Fedora Linux 17, the following instructions should still do the tricks for building the Compat bluetooth kernel module for Linux with kernel version of 2.6.x or above.

NOTE: this post is not about playing with the user space code that you may find on the bluez.org official site http://www.bluez.org/download/

1. download kernel code for the bluetooth module
This should be ported together with the kernel itself, but in case you have not yet had it on hand or been unable to find the source code, download from the site below

https://gforge.ti.com/gf/download/frsrelease/802/5435/ti-compat-bluetooth-2012-02-20.tar.gz

2. now once your followed the steps indicated on http://processors.wiki.ti.com/index.php/Open_source_Wireless_Connectivity_Bluetooth_components#Bluetooth_Modules, you will probably get stuck by the compilation with

make KLIB_BUILD=<Path To Linux> KLIB=${ROOTFS} install-modules

(Equivalence of it is to run "make bt" under the top source code directory.)

Error might be like some syntactical faults in the kernel headers this module depends on, and you may find you have no luck by applying the patch provided in the above site (http://processors.wiki.ti.com/images/8/8e/Compat-patch-zip.zip) , the only cure I had got that really was efficacious is to apply the following patch instead (thanks to the guy who posted it)
http://marc.info/?l=linux-wireless&m=132760196131230&w=2 (in case this link may be expired or moved away, I have pasted below)

This file was introduced in commit 2a11c8ea20bf850b3a2c60db8c2e7497d28aba99
and included in 3.1 and later kernels.  It includes <generated/autoconf.h>
itself, as well as some other definitions that are used elsewhere.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
 include/linux/compat-2.6.h |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/include/linux/compat-2.6.h b/include/linux/compat-2.6.h
index c23e94a..3ccd051 100644
--- a/include/linux/compat-2.6.h
+++ b/include/linux/compat-2.6.h
@@ -2,7 +2,9 @@
 #define LINUX_26_COMPAT_H
 
 #include <linux/version.h>
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,33))
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0))
+#include <linux/kconfig.h>
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,33))
 #include <generated/autoconf.h>
 #else
 #include <linux/autoconf.h>
-- 
1.7.4.4

(Copy it into a file named newpatch, say, and then apply it by "patch -p1 newpatch")

Thereafter, you should be able to get through "make bt" successfully".

3. However, when you get to "make btinstall" or later "make btuninstall" to toy around the Bluetooth loading or unloading, you can get more annoying warnings like:

/sbin/modprobe: invalid option -- 'l'

It seems not critical but will block the normal process of "installation" from being complete hence unsuccessfully installation of the new Bluetooth module you just made.

To get rid of them (I am showing you the reasons behind it since you may be interested more in the solutions right now, please Google that if you are indeed intrigued with that), use the following trick
(this is came up with on the basis of what was earlier posted by Artem Chekunov on http://comments.gmane.org/gmane.linux.kernel.wireless.general/87040)

touch /sbin/modprobe.sh

and then put the following into it and save.

--------------------------------------------------------------------------

#!/bin/bash

if [[ $1 == -l ]]
then

if [ -z $2 ]    
then

 find /lib/modules/$(uname -r) -name '*.ko' | \

 sed -e "s#\/lib\/modules\/$(uname -r)\/##g"
else

 find /lib/modules/$(uname -r) -name '*.ko' | \

 sed -e "s#\/lib\/modules\/$(uname -r)\/##g" | grep $2
fi

else
/sbin/modprobe $@
fi

exit 0

---------------------------------------------------------------------------

Note the last line I added (besides changes made somewhere else) is important to make sure that "make" can run completely through all expected steps.

Then do the following more steps:

chmod +x /sbin/modprobe.sh
alias modprobe=/sbin/modprobe.sh
echo "alias modprobe=/sbin/modprobe.sh" >> /etc/bashrc

cp Makefile Makefile.save
sed -i -e 's/^MODPROBE.*/MODPROBE := \/sbin\/modprobe.sh/g' Makefile

Now do what you like.

========================== End =====================================

Cracking problems during installation of FreeWRL under Fedora 13

2012-08-22T12:10:00.002-07:00

Starting from : http://freewrl.sourceforge.net/install_Linux.html

Can not find the gdk-pixbuf library or version is lower than required

2012-08-22T12:10:00.000-07:00

One more, maybe last in the nasty complaining list for building GTK+-2.22.1, prerequisite for GTK+, which might be complaining the lower version than required or simply loss of it:

1. yum -y reinstall gdk-pixbuf-devel.x86_64 gdk-pixbuf.x86_64
oops, no luck this time, ./configure of GTK still grouses there for missing it (on some platforms, this reintallation could only get the 0.22.0 version, for instance)

( if it wors ok now for you, stop here and congrutulations to you!)

2. download and built on source package

But gdk-pixelbuf-2.0 can NOT be found, how repulsively this costly trivial steps end like this!

Finally, it is a conclusion: you should build gtk-2.4, where gdk-pixbuf-2.0 will be included inside!!

ok, what else could we do but to follow it :

1.
go ftp://ftp.gtk.org/pub/gtk/v2.4/ :

wget ftp://ftp.gtk.org/pub/gtk/v2.4/glib-2.4.7.tar.bz2

bunzip glib-2.4.7.tar.bz2 && tar xvf glib-2.4.7.tar.bz2

cd glib-2.4.7.tar.bz2 && ./configure && make && make install

pkg-config --modversion glib-2.0
2.4.7

2.
wget ftp://ftp.gtk.org/pub/gtk/v2.4/pango-1.4.1.tar.bz2

same steps to install pango 1.4.1 as above

*** 'pkg-config --modversion glib-2.0' returned 2.4.7, but GLIB (2.26.1)
*** was found! If pkg-config was correct, then it is best
*** to remove the old version of GLib. You may also be able to fix the error
*** by modifying your LD_LIBRARY_PATH enviroment variable, or by editing
*** /etc/ld.so.conf. Make sure you have run ldconfig if that is
*** required on your system.
*** If pkg-config was wrong, set the environment variable PKG_CONFIG_PATH
*** to point to the correct configuration files
no
configure: error:
*** Glib 2.4.0 or better is required. The latest version of
*** Glib is always available from ftp://ftp.gtk.org/.

Overriding/overwriting and Overloading

2012-03-09T10:33:00.001-08:00

It is often asked how overriding/overwriting differs from overloading and there are many posts online to answer related questions. Here I am summarizing the difference between them to give an overview as much complete as possible.

(1) Overloading provides multiple signatures for the same method in a single class, with the return value being not seen as part of the signature of method; Overriding provides a different implementation of a method inherited from a base type.

(2) Overloading is decided at compile time and overriding is decided at runtime, Overriding is basically the point of polymorphism by inheritance.

(3) Overloading lets you define a similar operation in different ways for different data, Overriding lets you define a similar operation in different ways for different object types.

(4) Using overloading and overridding, you can acheive the concept of polymorphism. Polymorphism means "one name, multiple forms". Using one name u can do multiple of actions. Method overloading is a compile time polymorphism and Method Overridding is a runtime polymorphism. Compile time polymorphism means compiler knows which object assigned to which class at the compiling time. Runtime polymorphism means compiler didn't know at the compile time, it only knows at a run time.

(5) Overriding method appears in subclasses, having the same name and same parameter list as a superclass method. The access modifier for the overriding method may not be more restrictive than the access modifier of the superclass method.

=====================================

Similar to this topic, there is a differentiation between shadowing and overriding, found at

http://msdn.microsoft.com/en-us/library/ms172785(v=vs.80).aspx

how to retrieve the info of the compiler having built an ELF executable

2011-08-19T09:31:00.000-07:00

Sometime there happens to be a need for retrieving what is the compilation information, compiler version, say, of the compiler that was previously used for building an ELF executable.

There are two ways, no matter whether they are the real good ones.

1) objdump -s --section .comment <the executable>

2) strings -a <the executable> | grep -i -E "gcc|cl| $other possible clue for the compiler name"

Tracing the segmentation fault problem caused by glutBitmapCharacter or glutBitmapString

2011-07-24T19:18:00.001-07:00

When porting an openGL+freeGLUT program to a laptop running with an integrated on-board graphics card ( actually, a part of the chipset, the model is Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller in HP Presario CQ60 standard configuration ), a call in the code to glutBitmapCharacter always leads the program to perish in the runtime.

Built it in debug mode first and then trace the program with the dumped memory core. It is found that the problem can be traced to glBitmap -> libGL.so.xx -> /usr/lib/dri/i965_dri.so.

Tried dozens of "solutions" ranging from reinstalling many times of freeglut-2.6 to changing GLUT to the classic GLUT-3.7 following the instruction from http://original.jamesthornton.com/linux/HOWTO/Nvidia-OpenGL-Configuration/instglut.html, including debugging deeply in the code itself, trying different fonts and using glutBitmapString, for instance, just all end up with failures.

Finally, the installation of GLUT-3.7 through an indirect approach - by installing MesaLib (the another ordeal has been put in http://surfingtroves.blogspot.com/2011/07/defeating-mesalib-installation-issues.html)
give the sense of graphics driver issues. It really is!

Now, skipping the obscure discussions about the notorious graphics card driver problem in Linux ( this is true at least as far as I am concerned ), just show you the one of real "solutions":

go to /usr/lib/, mv i965_dri.so i965_dri.so.old.

get back the code, I am lucky to get the long gnawing problem solved. You should be as well if your case is similar to mine.

Defeating the MesaLib installation issues - not sufficiently high version of libdrm and then "915_EXEC_BLT" undeclared

2011-07-24T18:52:00.000-07:00

While obstructed by the tricky installation of GLUT-3.7 in Linux (Fedora 13/14 in this post's case), an easy expedient is to indirectly install MesaLib since this package should have already included GLUT-3.7 and thus the desirable installation of GLUT-3.7 can be achieved tortuously by installing MesaLib through the source package building.

However, there might be still other problems with the building installation itself of MesaLib, here are several candidates:

1. before generating the makefile, "./configure" can complains that the version of libdrm_intel is lower than 2.4.21 which is required to compile mesa.

---> download the package of libdrm from http://packages.pardus.org.tr/info/corporate2/devel/source/libdrm.html ,unpack it and go to "./configure", here you may get another obstacle, however, by failure in checking PCIACCESS. fix this easily by "yum -y install libpciaccess" and perhaps also "yum -y install libpciaccess-devel". Then "make" -> "make install". and get back to mesa

Unfortunately, the complaints did not disappear as most likely happens. This is a problem of package recognition previously encountered as the case of "http://surfingtroves.blogspot.com/2010/12/linux-fedora-upgraded-package-and.html" . For this instance, find libdrm_intel.pc ( should be found in /usr/local/lib/pkgconfig/ after installation, if not, copy from the source package of libdrm ( typically in intel/ ) and copy it to a directory like this), then add the containing path to the environment variable PKG_CONFIG_PATH. for example
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig:$PKG_CONFIG_PATH.

Then "pkg-config --modversion libdrm_intel" should confirm that the version is updated to suffice the installation of mesaLib.

2. "./configure" continues to grouches, but with missing of TALLOC this time. Fix it by installing libtalloc and libtalloc-devel using yum like above. and you should be able to get through it.

3. now, do the sure thing "make" , you are probably expected to get stymied again by the complaint like:

"error: I915_EXEC_BLT undeclared "

The is because the older version of the drm_intel library is still being used. Look at the compilation command line before this complaints, you can find "-I/usr/include/libdrm" therein. A simple fix is to copy the command line and manually compile again with "-I/usr/include/libdrm" changed to "-I/usr/local/include/libdrm" since drm_intel is installed to /usr/local by default.

4. "make install". And, done.

To check if GLUT-3.7 has been installed during the installation of mesaLib, look at /usr/local/lib/libglut* and /usr/local/include/GL/glut*.

Now you should be alreay there.

Can not hear from earphone on fedora linux ALSA Conexant

2011-07-24T18:02:00.000-07:00

1. check if the file /etc/modprobe.d/alsa-base exists, touch an empty one of this if not.

2. add following line to it :
options snd-hda-intel model=olpc-xo-1_5

3.save and reboot.

Then the problem should have gone.

Note that this may only do the tricks for exact this sound device
"Codec: Conexant CX20583 (Pebble HSF)". If it is not working for you, please refer to the original post at http://linux.derkeiler.com/Mailing-Lists/Ubuntu/2010-05/msg00541.html.

Many thanks to the original author.

Can not hear from earphone on fedora linux ALSA Conexant

2011-07-23T13:13:00.000-07:00

On how universities handle multiple GRE scores (how about taking GRE more than once) ?

2011-06-16T18:39:00.000-07:00

RESULTS FROM Google "more than one gre scores" or " Multiple GRE scores"
(first 50 pages according to the page-rank)

-------------------------------------------------------------------------------------------------------------------------------------------------------------

http://el-prod.baylor.edu/certain_doubts/?p=876
It is getting close to the time for graduating seniors to submit applications to PhD programs, and I’ve been reflecting again on our discipline’s practices in this regard. Especially, I’ve been thinking about the role of GRE scores in the process.
The role of GRE scores in any given graduate program is fairly obscure, but it is fair to say that there are institutional pressures to recruit students with higher GRE scores. There are various ways to succumb to these pressures, from a crass preference for higher GRE scores to a system in which first cuts are made on the basis of GRE scores. I don’t mean to attach any significance to the question of whether such practices amount to succumbing to pressure, however; my concern is with the practices themselves ...........................

-------------------------------------------------------------------------------------------------------------------------------------------------------------
http://www.vetmed.wsu.edu/prospectivestudents/admissionProcedure.aspx

* GRE percentile is calculated by averaging the percentile rank from the three sections of the general test (composite score). If an application contains more than one set of GRE scores, the committee will consider the highest section score. Only GRE scores received by the admissions office at the time of initial academic evaluation will contribute to Tier assignment.

-------------------------------------------------------------------------------------------------------------------------------------------------------------
http://chhs.gsu.edu/pt/faq.asp
15. I've taken the GRE multiple times. Which scores will you use?
We will use the highest score earned in each section of the GRE. For example, if your verbal test score was high the first time, we will use that score rather than your most recent verbal score (if lower). A minimum verbal score of 400 must be obtained. The required Analytical Writing Section score is 3.5. Scores cannot be more than five years old from the desired semester of entry.

-------------------------------------------------------------------------------------------------------------------------------------------------------------
http://www.yale.edu/graduateschool/admissions/faqstq.html
GRE scores are but one of many criteria used to evaluate an applicant. Individual departments practices may differ, but overall the best score from each section is used. However, you must submit ALL of your GRE scores in order to have the department consider the highest from each section.

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http://www.physics.ucsb.edu/education/graduate/prospective/faqsforapps.htm#mixgre

I have taken the GRE exams more than once. Can I mix and match the results?

GRE scores can not be mixed and matched. We will review only the most recent scores, regardless of the outcome.

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http://complit.uchicago.edu/graduate/applicationfaq.html
I have multiple GRE scores. How will my scores be interpreted?  ETS provides GRE scores from the past five years of an applicant's records. It is up to the discretion of the reviewers how they would like to account for these scores.

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http://economics.ucsd.edu/grad/gradAdm/admFaqs.php
What is your policy on GRE retakes?
Regarding GRE retakes, your highest scores will be considered of any test scores that are received before the admission application deadline. Remember that official scores from ETS are required. Copies are not accepted. Official scores must be received either by mail (postmark or carrier sent date) or electronically by the application deadline in order to be considered “on time.”

-------------------------------------------------------------------------------------------------------------------------------------------------------------
http://www.du.edu/korbel/admissions/howtoapply/faqs/

Can I take the GRE more than once?: Yes, you can take the GRE and TOEFL more than once. If there are multiple scores available, the Josef Korbel School takes the highest score for each section. Be sure to submit scores to our university each time you take the exam. For additional information about the GRE or TOEFL, including how to register or order your official test scores, please see: www.ets.org. The institutional code for the GRE and TOEFL is 4842.

How many scores does HGSE accept?

HGSE will consider up to two sets of official GRE scores. If candidates have taken the test more than twice, the admissions committee looks at the two most recent test dates. We encourage all applicants to self-report their scores on the online application, as well as request your official score report from ETS (our institution code is 3428). Additionally, HGSE does not average test scores - we look at each set of scores separately.

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http://www.econ.ucdavis.edu/graduates_faq.cfm

If I have taken the GRE exam more than once, how do you consider the scores?
	All of the scores will be looked at and considered. We will be able to consider your best scores of each section of the exam.

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http://depts.washington.edu/epidem/adm/FAQ_gre.shtml#mult
I took the GRE more than once, which score will you count?
We will count the best set of scores taken at one sitting. We will not consider the top score in each category if they are from different tests. If your scores went down in your most recent test, your chances of admission will be reduced.

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http://www.eecs.berkeley.edu/Gradadm/FAQA.htm
If I take the GRE more than once, which scores do you consider? The highest scores will be the most important to us.
How important is the writing/verbal portion of the GRE?
Though the math section will be more important in our review, any score less than a 400 on the verbal section of the test will be of concern.

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http://www.stat.columbia.edu/~cook/movabletype/archives/2009/01/taking-a-standa.html

When we have a grad school applicant who's taken the GRE or TOEFL multiple times, we typically just look at the highest score. It's my impression that pretty much everybody does this, even though basic statistical principles would suggest taking the average. Eric Rasmusen reminded me of this point in the context of the SAT, which apparently has changed its policy to encourage multiple test-taking even more, by allowing students to report only their highest score. Throwing away information--that doesn't sound like a good idea! But, as Rasumusen points out, it might make more money for the organizations that administer the test.
According to the linked news article, students "will have the option of choosing which scores to send to colleges while hiding those they do not want admissions officials to see." My question is: will their score report state whether they've chosen this option? If so, it should be possible to at least try to correct for the bias.
In any case, all this discussion makes me think we should be more careful about just looking at the maximum when our applicants take the GRE multiple times. And then there's the possibility of cheating. . . . I guess the real lesson is that these admissions decisions aren't going to be perfect, and we should think more about how to incorporate this perspective into our admissions process.

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http://www.google.com/url?sa=t&source=web&cd=106&ved=0CDcQFjAFOGQ&url=http%3A%2F%2Fwww.chemistry.ohio-state.edu%2Ffiles%2FAU%25202011%2520Admissions%2520FAQs.doc&rct=j&q=more%20than%20one%20gre%20scores&ei=DYv6TcH4LYTf0QHmkZmcAw&usg=AFQjCNFE4njAht7SSK0EFe2Wp_cnTB1Zog&sig2=95iSAr9Us0WUPOqz0QtB7A&cad=rja

If more than one set of scores from the GRE or TOEFL are reported, the committee will place the most weight during the review on the most recent score set.

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http://www.tuck.dartmouth.edu/admissions/admissions-faq/

I have taken the GMAT and/or GRE several times. Which score does the admissions committee consider?: The admissions committee takes into consideration your highest test score. The Tuck application allows students to report up to two GMAT and/or GRE test scores. If you have scored better on one test in the verbal section and better on the other in the quantitative section, we will consider your highest quantitative and highest verbal scores. Please refer to Instructions for applicants for more information.

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http://english.uchicago.edu/prospective/phd-checklist-and-faq
I have multiple GRE scores. How will my scores be interpreted?
ETS provides GRE scores from the past five years of an applicant's records. It is up to the discretion of the reviewers how they would like to account for these scores.

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http://www.cs.fsu.edu/current/grad/faq.php

I took the GRE more than once. Which score do you accept: the highest or the most recent score?

The highest GRE score is considered for admission.

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http://home.ubalt.edu/NTSBROSS/gre.html

If you do take the GRE more than once, it is important to remember that the institutions to which you apply may have to decide which of your scores to use in comparing you with other applicants. Institutional practices vary in this respect. In evaluating GRE scores as one factor in their admissions or fellowship decisions, some use the most recent scores, some the highest, and others average the scores earned in several tries.

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http://cilas.ucsd.edu/academics/graduate/faqs.html#p11
What is the average GRE score of applicants?

The Admissions Committee prefers applicants who have GRE scores over the 50th percentile. Because scores differ at each testing period, we mainly consider percentile rankings instead of raw scores. We take the highest of your GRE scores if the test has been taken multiple times, and we encourage applicants to retake the GRE if they feel it was not a good indicator of their ability.

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http://viterbi.usc.edu/admission/graduate/faq/submitted_application/admission-criteria.htm
Can I take the GRE more than once?
Yes, you can take the GRE more than once. If you have multiple GRE scores, we will consider the best score you obtained in each section.

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http://www.olemiss.edu/gradschool/GPC_handbook_1.html
When multiple GRE score reports exist, the most recent scores are considered applicable and individual sub-scores (in verbal, quantitative, and analytical reasoning) are not selected from among tests taken on different days.

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http://gradcollege.okstate.edu/faq/faq.html
How are multiple GRE scores treated?

GRE scores are one of the many criteria used to evaluate an applicant. Individual departments' practices may differ, but generally the last test score reported is the one used. Keep in mind that the score report will include all scores from the tests taken within the last 5 years.

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http://www.fordschool.umich.edu/prospective/masters_faq.php

How do you handle multiple GRE scores?

The Admissions Committee will be given all of the applicants' scores. We do not average them nor do we take the higher or lower scores. Improvement in scores will be taken into consideration.

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http://www.engr.wisc.edu/ie/prospective/grad/faq.html#21.

How important are GRE scores in admissions? Is there a minimum score required?

We try to develop an overall picture of the candidate and their chance of success in our program by considering all the application materials presented. Although we like to see the Quantitative portion of the GRE test scores above 90%, we do not weigh the GRE so heavily that scoring below that mark would cause us to deny a candidate. In general, students who are admitted into our graduate program have an overall score of 1200 or above.

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http://www.maxwell.syr.edu/ir/admissions/FAQ.aspx#29.

If you take the GRE exam more than once, our Admissions Committee will consider only the highest score of each section, whether that score was earned the first or second time the test was taken. Many applicants improve in at least one section the second time they take the exam.

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http://www.cs.rice.edu/gradinfo/faq.shtml
9. Multiple test scores

Q: What is your policy regarding multiple test scores? Which scores will be considered if the GRE, TOEFL, or TSE exams have been taken more than once?
A: The latest score.
10. GRE subject exam

Q: I am a Ph.D applicant, but lack a GRE subject test score. Can I apply as an MS candidate instead?
A: The GRE subject test is required for both MS and Ph.D applications.

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http://www.gsb.stanford.edu/mba/admission/test_scores.html
If you have taken the GMAT more than once, report only the score from one examination that you wish us to consider while reviewing your application. We do not average scores. The scores you report must be from the same testing session.

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http://ls.berkeley.edu/about-college/l-s-divisions/arts-humanities/diversity/prospective-students/graduate-record-exam
For applicants who have taken the GRE more than one time, you should be aware of how this situation may affect you. Usually, your highest score is acknowledged in each of the three components, but often all of your scores are also identified. I wouldn't worry too much about this. Admission committee members appear to take these situations in stride and understand the situations under which students are placed in test conditions.

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http://www.cs.vt.edu/graduate/prospective_students/application_guidelines

If I have multiple GRE scores, will you consider the best score? Or most recent score? If it is the best, will you consider the best of the total or best of individual scores?

It doesn't matter. The GRE is only one criterion used in admissions decisions. As the answer to the previous FAQ suggests, applicants with lower scores might be accepted and those with higher scores might be declined. You do not have to worry about your application being declined because we used the smaller GRE score.

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http://www.anderson.ucla.edu/x19460.xml#11.1
If I take the GMAT/GRE more than once, will the Admissions Committee average the scores or take the highest one?
We will see all of your scores but will take your higher score if you take the test twice. If you take the test more than twice, we consider all scores, but will not average them.

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http://www4.gsb.columbia.edu/mba/admissions/applynow/apprequirements#GMAT
Be sure to self-report your GMAT score when completing your application. If admitted, you must submit an official score report via www.mba.com. The Admissions Committee will consider only your highest score when reviewing your application, but will not combine subscores from multiple exams into a single composite score. Columbia Business School’s GMAC code is QF8-N6-36.

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http://som.utdallas.edu/academicAreas/isom/opMgmtPrograms/faq.php

In case of more than one GMAT score, would you consider the average or the best score? For MS SCM program, we consider the best GMAT score.

-------------------------------------------------------------------------------------------------------------------------------------------------------------
http://socialsciences.uchicago.edu/prospective/admissions/admissions-application.shtml
In the cases of multiple tests, the overall best test date is used for review purposes.

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http://www.hds.harvard.edu/afa/apply/faq.html#Can%20I%20take%20the%20GRE%20multiple%20times?

Can I take the GRE multiple times? If you receive multiple scores from me, how will you determine which ones to consider for my application?
When possible, we suggest that you prepare carefully and take the GRE once. If you chose to take the GRE a second or third time after sending us an official GRE score report, it is possible that the Admissions Committee will complete its review of your application before the additional scores arrive. If we receive multiple sets of scores from you before the application deadline, the Admissions Committee will consider all scores received. Remember, GRE scores are only valid for five years. If you submit invalid scores, your application will be considered incomplete

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http://www.wharton.upenn.edu/doctoral/admissions/application-requirements.cfm#Standardized_Test_Scores
We evaluate only GMAT and GRE results from tests taken prior to the receipt of your application. The highest score is used — we do not combine multiple scores.

-------------------------------------------------------------------------------------------------------------------------------------------------------------
http://che.engin.umich.edu/graduateprogram/graduateadmissions/gradfaq.html#scores
If I take the GRE more than one time which score will you take? We look at the applicant's highest GRE score.

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UC Davis says "When you take the GRE multiple times, we consider the highest scores in each section for examinations taken within the five-year period."
Source: http://www.vetmed.ucdavis.edu/studen.../faqs.html#q21

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Cornell says "Cornell also has a policy of using your best test composite scores from multiple tests (even if your best scores in the various sections were not earned on the same test date) to help our applicants feel less anxious about any one test. If you experience test anxiety, you may leave an examine knowing you may return for a new examine without being penalized in Cornell's DVM Admissions selection process."
Source: http://www.vet.cornell.edu/admissions/prep.htm

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Iowa State says "The one test that gives you the best score is used."
Source: http://www.vetmed.iastate.edu/prospe...aspx?id=988#26

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Louisiana State says "When the GRE has been taken more than once, the highest score from a single test date will be used."
Source: http://www.vetmed.lsu.edu/admissions...qs.htm#re-take

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Michigan State says " When the test has been taken more than once, only the higher composite score will be added to the applicant's credentials."
Source: http://www.cvm.msu.edu/student-infor.../gre-and-toefl

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North Caroline State says "If an applicant takes the test more than once, the highest total score is used from a single testing date, not the highest of each section."
Source: http://www.cvm.ncsu.edu/studentservices/admissions.html

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Ohio State says " We take the highest score from one exam. "
Source: http://www.vet.ohio-state.edu/2699.htm#q19

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Washington State says "GRE scores are calculated by averaging the percentile rank on all 3 sections of the general test (composite score). If an application contains more than one set of GRE scores, the committee will consider the highest composite score. Only GRE scores received by the Admissions Office at the time of initial academic evaluation will contribute to Tier assignment. Scores received later will be used in the final evaluation."
Source: http://www.vetmed.wsu.edu/prospectiv...Procedure.aspx

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Western University says "If taken multiple times, all scores will be considered, but more weight will likely be placed on the later score."
Source: http://www.westernu.edu/xp/edu/howto...he_GRE_or_MCAT

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http://www.vet.upenn.edu/admissions/faq.html

"When considering scores from multiple test dates, we will take the highest combined verbal and quantitative scores from the same test date."

building installation of freeglut ------ problem with /usr/lib/libGL.so.1 or /lib/libm.so.6

2011-05-27T13:49:00.000-07:00

When setting up freeglut with the source code package downloaded from sourceForge in the Fedora Linux environment, there always complains in the link step about loss of either of following two dynamically-linked libraries on the linker's command line:

/usr/lib/libGL.so.1
/lib/libm.so.6

The typical prompt would be like the lines as follows:

freeglut is defined in DSO /usr/lib/libGL.so.1 so try adding it to the linker command line

A very gauche approach is to edit each Makefile spread over different levels of directories in the source code root, by changing each "CC=gcc" line to "CC=gcc /usr/lib/libGL.so.1 /lib/libm.so.6". Obviously, you will need much pissy manual work to treat this nasty problem.

Here what I would like to share is a cheaper yet perky way, maybe not that paradigmatic though, to the quick solution:

1. enter /usr/bin/ (or somewhere else gcc lies, the location can be retrieved by whereis gcc );
2. mv gcc gcc_org
3. touch gcc and add following lines in it:
#!/bin/bash

/usr/bin/gcc_org $@ /usr/lib/libGL.so.1 /lib/libm.so.6

4. chmod +x gcc

Now get back to glut source package directory and follow the original instruction, that is, "./configure" -> "make && make install".

You should not expect further problems until everything will be set up well there.

After done, do not forget to clean up the your cheating spot : move to /usr/bin,
and "mv gcc_org gcc".

A TUI library for Dos/Windows

2011-03-28T20:30:00.000-07:00

A Text User Interface Library in C++ for DOS/Windows. Useful for building light-weighted TUI based applications.

http://sourceforge.net/u/haipengcai/wikituidos/Home/

Why vim not search STL headers?

2011-02-08T12:14:00.000-08:00

In vim it is common to open a header in place, which is really a handy feature for browsing a directory hierarchy.

But you might find this functionality seems to fail with C++ STL headers : when the cursor is blinking under "#include <iostream>", say, and your hitting 'gf' will not respond by entering that header but engender a grouch like following instead:

"E447: Can't find file iostream in path".

In actuality it is quite easy to resolve this problem by riffling through vim manual.

Treatment:

open the rc file of vim, for instance, /etc/vimrc, add following setting :

set path = **,/usr/include/c++/**

provided your c++ STL headers are hoarded in /usr/include/c++.

reopen the source code you were previously browsing around and try "gf" again, it should work now! It is really that piece of cake! Really extensible is vim!

remove empty line by sed or in vim

2011-02-08T12:00:00.000-08:00

In vim, following the same trick for general sustitution:

:%s/^[\ \t]*\n//g

By sed on the command line:

cat orgfile | sed /^$/d

Enable X Shared Memory Extension Pixmaps

2011-01-08T10:03:00.000-08:00

Definitely not encouraged to use, sometimes this feature is needed for using certain applications what depends on this deprecated X window extension.

Found the solution on http://fxc.noaa.gov/FSD-NVIDIA-OB9-FXC.htm. More precisely, an example illustrating the details with Nvidia series on Fedora 14 is shown as follows.

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 260.19.29

# (buildmeister@swio-display-x86-rhel47-04.nvidia.com)  Wed Dec

# 8 12:27:39 PST 2010


Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
    FontPath        "/usr/share/fonts/default/Type1"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/input/mice"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

    # generated from data in "/etc/sysconfig/keyboard"
    Identifier     "Keyboard0"
    Driver         "kbd"
    Option         "XkbLayout" "us"
    Option         "XkbModel" "pc105"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0
    VertRefresh     43.0 - 72.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    Option    "AllowSHMPixmaps" "true"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

The enabling appendix is simply the single line below.
Option "AllowSHMPixmaps" "true"

Then reboot the system to make it effect.

Following code snippet could be used for verifying the availability of this feature:

int vmajor;

int vminor;
bool vpixmap;
bool shm_flag;
if (XShmQueryVersion(window->getDisplay(),&vmajor,&vminor,&vpixmap) != True) { 
    cerr << "X Shared Memory Extension not supported." << endl;
    shm_flag=false;
}
else if (vpixmap != True) { 
    cerr << "X Shared Memory Extension Pixmap not supported." << endl;
    shm_flag=false;
}
else {
    // do what is relying on the MIT-SHM feature from here on
    ......
}

How to get the screen resolution in Linux C (and more X window information)

2011-01-06T08:35:00.000-08:00

Linux C: get the screen resolution and window size

Happened to necessitate the retrieval of information about the screen of the canonical X window system (X11) in use while I am employing Fedora Linux release 14.

Some guys (or gals maybe) suggest achieving this by GTK calls like gdk_screen_get_resolution or the like, I will prefer to using the legacy routines of Xlib for accessing to the X window information. For at least one thing, the X window system is presumably more likely to be installed in Linux OS than is the GTK/GTK+ libraries in my view.

Actually it is quite simpler than it might be postulated to be:

// -----------------------------------------------------------
// Purpose : simply retrieve current X screen resolution and 
//    the size of current root window of the default 
//    screen of curent default window
// -----------------------------------------------------------

#include <X11/Xlib.h>
#include <stdio.h>

int getRootWindowSize(int *w, int *h)
{
 Display* pdsp = NULL;
 Window wid = 0;
 XWindowAttributes xwAttr;

 pdsp = XOpenDisplay( NULL );
 if ( !pdsp ) {
  fprintf(stderr, "Failed to open default display.\n");
  return -1;
 }

 wid = DefaultRootWindow( pdsp );
 if ( 0 > wid ) {
  fprintf(stderr, "Failed to obtain the root windows Id "
      "of the default screen of given display.\n");
  return -2;
 }
 
 Status ret = XGetWindowAttributes( pdsp, wid, &xwAttr );
 *w = xwAttr.width;
 *h = xwAttr.height;

 XCloseDisplay( pdsp );
 return 0;
}

int getScreenSize(int *w, int*h)
{

 Display* pdsp = NULL;
 Screen* pscr = NULL;

 pdsp = XOpenDisplay( NULL );
 if ( !pdsp ) {
  fprintf(stderr, "Failed to open default display.\n");
  return -1;
 }

    pscr = DefaultScreenOfDisplay( pdsp );
 if ( !pscr ) {
  fprintf(stderr, "Failed to obtain the default screen of given display.\n");
  return -2;
 }

 *w = pscr->width;
 *h = pscr->height;

 XCloseDisplay( pdsp );
 return 0;
}

int main()
{
 int w, h;

 getScreenSize(&w, &h);
 printf (" Screen:  width = %d, height = %d \n", w, h);

 getRootWindowSize(&w, &h);
 printf (" Root Window:  width = %d, height = %d \n", w, h);
 
 return 1;
 
}


/* gcc -o $@ $< -lX11 */


/* set ts=4 sts=4 tw=100 sw=4 */

You can also retrieve more information about the X window system you are currently using, such as display name and the tag of vendor.

// -----------------------------------------------------------
// Purpose : simply retrieve current X windows information
// -----------------------------------------------------------
#define XLIB_ILLEGAL_ACCESS
#include <X11/Xlib.h>
#include <stdio.h>

int main()
{

 Display* pdsp = XOpenDisplay(NULL);
 Window wid = DefaultRootWindow(pdsp);

 Screen* pwnd = DefaultScreenOfDisplay(pdsp);
 int sid = DefaultScreen(pdsp);
 
 XWindowAttributes xwAttr;
 XGetWindowAttributes(pdsp,wid,&xwAttr);

 printf (" name : %s\n vendor : %s\n", pdsp->display_name, pdsp->vendor);
 printf (" pos : (%d, %d), width = %d, height = %d \n",
   xwAttr.x, xwAttr.y, xwAttr.width, xwAttr.height);

 XCloseDisplay( pdsp );
 
 return 1;
}


/* gcc -o $@ $< -lX11 */
/* set ts=4 sts=4 tw=100 sw=4 */

Note that here "#define XLIB_ILLEGAL_ACCESS" was used for accessing to some of the data member in the Display structure in C.

For more data member accessible, see the definition/declarations in the header /usr/include/X11/Xlib.h.

PS: It is thankfully in the courtesy of http://www.craftyfella.com/2010/01/syntax-highlighting-with-blogger-engine.html to make the code snippets I posted above have a highlighted effect and look organized more trimly (otherwise it is always bit of mangled!) Thanks to craftyfella!

Can not find man page for GLUT routines in Linux?

2011-01-03T17:35:00.000-08:00

I made up the man page for GLUT (so that I can ^K to call the API manual out while the cursor is on the words symbolizing GLUT routines) by the simplest way:

sudo yum list "*glut*"

more than a couple was found and following two are among the alternatives:

sudo -y install freeglut freeglut-evel

now enter into vim again and try ^K on "glutWindowSize" for instance, check if it works now.

Fix bugs for Buidling installation of G3D 7.01 in Fedora 14

2011-01-03T16:19:00.000-08:00

Today I am porting such and such a project which is dependent on G3D and for historical reasons this project could not work with other versions of G3D including the latest ones but versions before 8.0 since it calls some of the routines in the Libraries whose prototypes had been modified!

In conclusion, we have two bugs to fix before the G3D 7.01 library can be successfully built from the downloaded source code found at http://sourceforge.net/projects/g3d/files/g3d-cpp/7.01/G3D-7.01-src.zip/download in Fedora 14. I deem the same problems and solutions may as well be portable to other Linux distributions and various versions of specific distribution.

1. Edit GLG3D.lib/include/GLG3D/Discovery2.h, add the header including definition of the macro "INT_MAX" which was referred at line 68 in this file, where the first problem you will run across in the first try of building using "./buildg3d all" or "buildg3d --install all", or so forth the similar.

I simply added "#include <limits.h>" right after "#include <string.h>", actually an c++ header equivalent is "climits".

(Where is "INT_MAX", "LONG_MAX", etc, defined?)
I found the container header of this macro at http://www.fredosaurus.com/notes-cpp/90summaries/summary-headers.html, you may find it useful further in the future.

2. In order to get a complete installation, test code should not be skipped either, so this fix is necessary:

in tools/viewer/MD2Viewer.cpp : 108, change
currentPose = MD2Model::Pose::Pose(MD2Model::STAND, 0);
into
currentPose = MD2Model::Pose(MD2Model::STAND, 0);

I am bit of wondering why there the class Pose 's constructor should be called in this explicit way with this originally buggy code.

3. now get back to the source directory (where ./buildg3d lies),
./buildg3d --install all"

then the library will be installed straightforwardly.

A Funny Time Varying VIM color scheme switching

2011-01-03T13:44:00.000-08:00

Vi/vim is really the most popular editor under Linux esp. for those advanced users or Linux fans, even though there are dozen of other featured ones including visual editors and the most worthy of mentioning, Emacs for programming gurus.

Here I just got a whimsy yet actually a fortuitous idea, to make this editor of daily use to be adaptive with current local time periods such as morning, noon, evening and other phases of a day.

The snippet meant to be placed in or tailed at the vim configuration file, as is mostly the /etc/vimrc or $HOME/vimrc, will make the vim editor apply different color scheme that is meaningfully in accordance with the time of period when vim is launched. Additionally, color schemes for other time of period than morning and evening will be changed with the weekday.

" # intelligent colorscheme switching
let weekday=system('date +%u')
let hour=system('date +%H')

" if the shell command gets any exception during execution, nothing will be

" done on color scheme setting
if !v:shell_error


   " in other time slots than mornings and evenings, scheme to be applied depends

   " on which the weekday it is today, beginning from 1 as Monday, through 6 as

   " Saturday and Sunday numbered as 0
    if     1== weekday
        let coloration="elflord"
    elseif 2 == weekday
        let coloration="koehler"
    elseif 3 == weekday
        let coloration="slate"
    elseif 4 == weekday
        let coloration="zellner"
    elseif 5 == weekday
        let coloration="torte"
    elseif 6 == weekday
        let coloration="ron"
    else "Sundays
        let coloration="blue"
    endif

    " exert the color scheme application
    execute "colorscheme ".coloration

    " in mornings, alwasy using the "morning" scheme
    if hour >= 7 && hour <= 10
        let coloration="morning"
    " in evenings, alwasy using the "evening" scheme
    elseif hour >= 18 && hour <= 23
        let coloration="evening"
    endif

endif

Just give it a try, you may be intrigued with use of it afterwards like me!

-----------------------------------
other interesting links
-------------------------------------

Full range of vim color scheme implemented in a Google code project
http://vimcolorschemetest.googlecode.com/svn/html/index-c.html

A find-tweaked color scheme for Mac:
http://blog.toddwerth.com/entries/show/8

Install Nvidia Driver (non Gefore series) in Fedora 14

2011-01-01T19:24:00.000-08:00

Intro:

While here places a complete guide that is already great for novices in Fedora community at http://www.if-not-true-then-false.com/2010/fedora-14-nvidia-drivers-install-guide-disable-nouveau-driver/, following text will act as a complementary instruction for those who are using Nvidia Driver Card other than in the Geforce / Geforce FX series, Quadro FX, for instance. (some parts actually are learned from the this page)

Steps:

1. update to the latest kernel and restart the OS

yum update kernel*
reboot

2. make sure a correct xorg configuration, i.e. /etc/X11/xorg.conf, contains things about nvidia like the following

Section "Files"

    ModulePath   "/usr/lib64/xorg/modules/extensions/nvidia"
    ModulePath   "/usr/lib64/xorg/modules"
EndSection

(If for 32bit platform, use lib instead of lib64 in the paths above)

(If the xorg.conf file does not exist before, simply create it and add the stuff above)

3. Change Configuration of the Grub Bootloader by changing the current /boot/grub/grub.conf into text

like the following

default=0
timeout=5
splashimage=(hd0,0)/boot/grub/splash.xpm.gz

hiddenmenu

title Fedora (2.6.35.10-74.fc14.x86_64)
 root (hd0,0)
 kernel /boot/vmlinuz-2.6.35.10-74.fc14.x86_64 ro root=UUID=e36dbe41-49ac-458f-8942-ba3fbdd22e32

 rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16

KEYTABLE=us rhgb quiet rdblacklist=nouveau nouveau.modeset=0
 initrd /boot/initramfs-2.6.35.10-74.fc14.x86_64.img

title Fedora Linux 14 (2.6.35.6-45.fc14.x86_64)
 root (hd0,0)
 kernel /boot/vmlinuz-2.6.35.6-45.fc14.x86_64 ro root=UUID=e36dbe41-49ac-458f-8942-ba3fbdd22e32

rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16

 KEYTABLE=us rhgb quiet
 initrd /boot/initramfs-2.6.35.6-45.fc14.x86_64.img

title windows 7
 rootnoverify (hd0,3)
 chainloader +1

the key is the blued text, which is added to disable the default display driver : nouveau. If this is

missed, you will be told in the step 4 below that the installer can not proceed due to the nouveau is not

disabled.

4. download driver from Nvidia official site, for linux x86_64 we are using

http://us.download.nvidia.com/XFree86/Linux-x86_64/260.19.29/NVIDIA-Linux-x86_64-260.19.29.run

for now, wget it to a handy location, /root, say.

5. reboot,  then select the latest kernel item, and

 press "e" to edit it

 choose the "kernel /boot/vmlinuz-2.6.35.10-7...." line and press "e" to edit again

 append "single" to the line and press enter to get back to the previous interface

 press "b" to trigger the bootstrap

6. now that get in the Level 1 (single user mode), enter Level 3 (I did not check if this is necessary)

by "/sbin/init 3"

7. Run the installer

 sh /root/NVIDIA-Linux-x86_64-260.19.29.run -a

(if you are installing for the first time, you might already nvidia-installer on you machine,

then you don't need to download beforehand, instead a simpler way is :

nvidia-install -a --update

you can by this get the latest driver and install it. but this will demand a network access

of course, see this page (http://surfingtroves.blogspot.com/2010/12/linux-access-network

-service-in-single.html ) for enabling network access in the single user mode, as is suitable

for being at Level 3.

8. when finished, restart, and the installation should be well done.