Unix Programming

Xlib question - efficient way to get pixel value?
Hi I need to constantly get the pixel values in a drawable. The only way I can see to do this is call XGetImage() then XGetPixel() , but calling XGetImage() every iteration seems horribly inefficient. Is there a way I can get a pixel value directly instead of having to copy the entire window contents each time? ... 16 Oct 2009 05:18

ksh: /usr/bin/find: arg list too long
Unix version is: SunOS 5.10 Generic_141414-02 sun4v sparc SUNW,T5240 I am encountering the following error: 'ksh: /usr/bin/find: arg list too long' for this script: #!/bin/ksh FILE_AGE_CRITERION_IN_DAYS=$1 FILE_NAME_PATTERN_TO_MATCH=* DIR_TO_CLEAN=$3 LOG_DIR=$4 FILES_DELETED_COUNT=0 for FILE in `f... 15 Oct 2009 17:12

weird environ
On NetBSD 5.0.1 getpwuid fails unless I set a dummy environment variable, which apparently causes the environ memory to be reallocated. I guess this is just a NetBSD bug, but it leads to another question. What's the preferred way to clear the environment, in the absence of clearenv()? Google found this: h... 10 Oct 2009 10:32

How to add GUI to command line
Hello, My problem: Suppose that there is no GUI front-end to a tool say nmap (nmap has a gui front-end, but lets assume that it doesn't) then, how can I make a gui to the various commands in nmap. There are various flags (and I could make a check box to add each) but how to connect(communicate) with the command... 4 Oct 2009 19:57

ANN: Seed7 Release 2009-10-04
Hello, I have released a new version of Seed7: seed7_05_20091004.tgz In the Seed7 programming language new statements and operators can be declared easily. Types are first class objects and therefore templates/generics need no special syntax. Object orientation is used when it brings advantages and not in plac... 4 Oct 2009 15:29

Using recvfrom with a raw socket on linux
Hi I am writing some code to read ethernet frames off of raw socket on linux created this: socket(PF_PACKET,SOCK_RAW,htons(ETH_P_ALL) The question I have is the behaviour of recvfrom() in this situation. My first question is will it only ever read 1 frame per call or could more than 1 frame appear in th... 25 Sep 2009 07:33

mt
I have mt on my linux system and I think it's from back when tapes were used. How was mt used? Was it to create executables or slpit up a directory tape? I would like to create a file that knows where what execuatables and binaries are where? Bill ... 25 Sep 2009 11:57

broken pipe when reading and writing a pipe
hi I am trying to do a simple task: I have a buffer, I want to write this buffer as the stdin of a command, say "tac", and capture the output from the stdout and save to another buffer. after searching examples and playing a little bit, I wrote the a function (see below). However, it gave me a "Broken pipe" er... 19 Sep 2009 17:01

Need to use streams/buffers, but NOT related to stdin, stdoutor to files
WANG Cong wrote: On 09/12/09 20:23, Ramon F Herrera <ramon(a)conexus.net> wrote: I have looked all over the net for this, but all the hits I get are about cout, cin or streams linked to disk files. The feature that I need is in-core (boy, that's an ancient term) streams and buffers. Bac... 17 Sep 2009 21:33

[Help needed] Locking mechanisms in Linux
I need a little help regarding lock mechanisms in Linux. I want to participate in Linux Kernel development. I am facing an issue. Could you please help/suggest me. Problem Scenario: Same file is being shared by multiple processes. Any process can create the file (multiple owner case). Whenever a process c... 16 Sep 2009 12:57