C is a general-purpose computer programming language used for operating systems, games and other high performance work and is clearly distinct from C++. It was developed in 1972 by Dennis Ritchie for use with the Unix operating system.

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Cross compiling a software module

I'm trying to compile dropbear with the GNU ARM tool chain. I've went through this guide and managed to successfully build all the required tools. They are located in a directory: ...
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35 views

Linux server as a target for my C code [closed]

How to use a linux server as a target for my C code written on a different (Windows) machine. Including step by step debugging and etc... All that with Eclipse Env.
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1answer
146 views

Compiling sources with a non-default compiler

I need to implement an authentication scheme on an embedded device and require gmp in order to perform large integer operations. After downloading the sources they must be compiled with a proprietary ...
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146 views

custom gcc install include files

I have a custom installation of g++ 4.8.1 in my home directory. However the include files in that installation have no extensions! (except for tgmath.h, fenv.h, complex.h, and cxxabi.h) Thus even if ...
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1answer
206 views

How to determine which Berkeley DB version is used for RPM's database?

I am attempting to read and write the RPM database located in /var/lib/rpm under CentOS 5, and eventually other system types (CentOS 6, RHEL, etc.) The problem is that I don't know what version of ...
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1answer
947 views

How do I check if FFTW installed correctly?

I tried to install FFTW on my system (Ubuntu 12.04) using the rather unclear instructions on this website, and now I want to check if it worked. (FFTW is a C subroutine library for computing the ...
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138 views

I can fix/repair small damaged tar.gz files using fixgz but it doesn't work on bigger files

The title tells it. I have some damaged .tar.gz files, most of them are pretty small (smaller than 1-2gb) but 4 of them are bigger and fixgz cant fix them, when i run fixgz for those big files, it ...
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3answers
87 views

Are there obvious differences between learning C on OSX and learning C on Ubuntu?

I'm a python programmer, and today I start my journey of C. Now I'm using OSX, with Ubuntu in my Virtual machine, meanwhile our production servers are using CentOS. I suppose these three systems ...
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3answers
2k views

How to calculate the memory consumed by a “C” program in linux

I have written two C programmes one is using function pointer, and the other without function pointer. Now i want to know the memory consumed by the two programmes , to see how memory can ...
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0answers
345 views

how to increase Stack Size of a running program in C

I am trying to identify any way if we can increase the stack size of my running program after getting SIGSEGV. I know we can increase the size of stack by ulimit -c but, that did not solve this ...
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1answer
42 views

Meaning of '&' in C (here in linux kernel function-like Macros) [closed]

#define TCP_SKB_CB( __skb ) ((struct tcp_skb_cb *)&((__skb)->cb[0])) What does the & mean in this context?
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2answers
194 views

When does cat finish reading from a pipe?

Given the following code, why does cat only print the contents of the pipe after I've typed \n or CTRL+D? What are the conditions for cat to actually print what it read? #include <stdio.h> ...
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1answer
354 views

How can I (easily) map a block device node to the directory it's mounted on?

I need to find (in C or C++) the used space on a filesystem (Linux) when being provided only with the disk block device name and the partition number. For most filesystems I can go: Craft a dev ...
3
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1answer
359 views

Memory layout of dynamic loaded/linked library

when loading a shared library in Linux system, what is the memory layout of the shared library? For instance, the original memory layout is the following: +-----------+ |heap(ori) | +-----------+ ...
3
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1answer
178 views

Io redirection vs file logging performance c/c++

Is there a performance difference from a latency point of view if we do a regular printf and redirect stdout to a file when running the program ( e.g., ./a.out > log.txt 2>&1 ) vs using fprintf ...
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1answer
139 views

Can I use LXC library in my c program?

Currently, I am designing a c program that will create multiple container and put different applications into them separately to achieve isolation. Is it possible to leverage LXC library to it? I ...
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1answer
759 views

Can I write C programs for Linux on OS X?

In case I'm writing a program (of any kind) in C, that is meant to be run on Linux environment, can I write it under OS X? (concurrency wise for example) I'm asking this because I like programming in ...
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2answers
368 views

The «sh» being launched with execl() becomes a zombie

I am spent whole half a day, but still couldn't figure, why is the dash being launched with execl call just becomes a zombie. Below is a minimal test case — I'm just fork a child, make a duplicate of ...
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1answer
92 views

What happens to TCP when a write fails to enqueue with the device tx ring?

Lets say the device tx ring is full and you do a normal C non blocking write(fd, buff) to enqueue data in the TCP SND buffer. What happens when this fails? In UDP - the packet would be dropped but ...
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1answer
96 views

Distributing app with .so files?

I'm trying to make a game in C with SDL and OpenGL. Q: Will my game run on computers without SDL installed if I ship the .so files in my game folder? I mean adding the .so files somewhere in the game ...
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1answer
1k views

why is “timer_t” defined in “time.h” on Linux but not OS X

While I was reading a C source code files, I found this declarations. (This source code was written for linux system program. This is very important information) #include <time.h> #include ...
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1answer
503 views

Reading the program header contents of an ELF file

How is it possible to extract loadable program headers individually from ELF files? By examining a binary using readelf one can get output similar to: $ readelf -l helloworld Elf file type is EXEC ...
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1answer
63 views

introduce a c script in a bash file [closed]

My problem is to recover data keyed in text file in bash. I seek the command that can perform this task and I used sed, awk and even cut but I have not succeeded. One friend of mine suggested to ...
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1answer
85 views

How do I execute a parted command with a C function?

I would like to execute the Linux command "parted" through a C language function? I am using Linux Ubuntu , eclipse. Thanks!
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0answers
23 views

How to obtain block device label [duplicate]

I have a tricky problem. I have a block device connected to SLES11, it is present in /proc/partitions but it is not mounted (not present in /proc/mounts). From C code I want to find the block device ...
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1answer
2k views

Reading the contents of an ELF file (programmatically) [closed]

I am trying to retrieve the contents of an additional section within an ELF binary. At this point, I'm using the following code to retrieve the name of each section: #include <stdio.h> #include ...
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2answers
248 views

Pulling log messages for a particular log in systemd journal?

I was wondering if it is possible to pull log messages for a particular log with systemd's journal logging. For example, when I open a log in C, openlog('slog', LOG_CONS | LOG_PID, LOG_LOCAL1), to ...
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1answer
185 views

How to run smartctl as root without switching to root?

I have this C code that runs smartctl command and takes its output: #include <iostream> #include <cstdio> #include <cstdlib> using namespace std; int main() { cout << ...
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1answer
219 views

Trying to make a Universal Makefile

I'm working on my own netfilter module for the first time. According to internet documentation, The simplest module contains the following C code: //'Hello World' kernel module, logs call to ...
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3answers
275 views

loop test strings to see if input is valid for C program input

For example I have a file filled with some pretty gnarly strings. 12345678900 1111111111111111111111111 ...
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1answer
521 views

C/C++: Running multiple commands as root

I want to execute commands within my C program. However, I need root priviliges to create some folders. I run the following: system("echo <rootpass> | sudo cd <folder> && make ...
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1answer
379 views

how to return file descriptor in c [closed]

I am confusing with this. fp=fopen(filename,mode); what is the value fopen() return to fp. is that value is file descriptor integer? is fp called as stream ? if not how to return a ...
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1answer
290 views

How to select read/write time and again? [closed]

This program only waits one time and I don't understand why. Actually, I don't think this question should be put on hold as off-topic. #include <stdio.h> #include <sys/types.h> #include ...
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2answers
102 views

linux setuid does not work

I am learning linux suid,so I have written a small c program with the following content to test it #include<stdio.h> int main(){ system("echo 100 >> test.txt"); return 0; } -rwsr-xr-x 1 ...
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1answer
6k views

“fatal error: stdio.h : No such file or directory” while compiling a C file [closed]

Trying to compile following code in terminal i got root@debian:/home/mz2/Documentos# LANG=C ./soma.c ./soma.c: line 2: syntax error near unexpected token `(' ./soma.c: line 2: `int soma (int a, int ...
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109 views

keyboard still working after calling free_irq(1, NULL);

I'm developing a kernel module which free the IRQ number 1 in order to disable the keyboard in Intel architectures. according to wikipedia the IRQ 1 is used for keyboard. but after building and ...
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4answers
5k views

How to dump a binary file as a C/C++ string literal?

I have a binary file I would like to include in my C source code (temporarily, for testing purposes) so I would like to obtain the file contents as a C string, something like this: \x01\x02\x03\x04 ...
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1answer
136 views

how to define the top dir in automake system?

I usually use a typical steps to generate the makefile, and firstly I use the "build.sh init" to generate the configure file, and then I use "configure" to generate the makefile with makefile.am file. ...
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1answer
2k views

Cabal error: Cannot run c compiled programs

I have an old version of cabal-install so I downloaded cabal-install 1.20 and When installing it errors out. Additional note: ghc 7.8.3 OS: CentOS 6.6 Error: Building network-2.4.2.3... ....... ...
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1answer
808 views

Cannot find -lgcc

I'm trying to compile my next basic c program after hello-world. This contains two supporting modules. I have Ubuntu running in a VM through VirtualBox on a mac. Everything is up to date but I ...
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0answers
6k views

Getting “cannot open shared object file: No such file or directory” error while run time

I have successfully compiled the file but now I am getting following errors export LD_LIBRARY_PATH=/opt/mcr/v717/sys/java/jre/glnxa64/jre/lib/amd64/server/:D_LIBRARY_PATH ./invoke ./invoke: error ...
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1answer
49 views

-fPIC Flag System-wide?

Position Independent Code means that the generated machine code is not dependent on being located at a specific address in order to work. and the jumps are relative. So is it OK to declare -fPIC ...
2
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1answer
135 views

How to compile manual files .1

I have .c, .h, and .1 files, how can I compile them together in one executable file. Everything clear with .c and .h files, but I have also .1 as I can see from the content it is used for manual, how ...
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2answers
201 views

How can I link my C program against the Arb library?

I tried to compile the program Testing Li’s criterion in Ubuntu. However, when I do gcc demo.c, I get the output as, demo.c:2:19: fatal error: fmpcb.h: No such file or directory #include "fmpcb.h" ...
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1answer
2k views

Linking a static library when compiling a C program

I'm linking *.a file with *.c file, so I have used the following command: gcc abc.c -l ad.a (here abc is the C source file and ad is the static library file) then after executing the following ...
3
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1answer
176 views

Read .desktop files programmatically [closed]

I would like to make a C program (GTK) that reads a .desktop file. The only thing I need from the .desktop file is the exec command. Is there something built into GTK that would allow me to interact ...
2
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2answers
270 views

assign output of a c program to a shell variable: token error

I have a shell script to run several times a .c program ('switch') which admit 3 input paramenters. I want to run the program 4 times passing values {4,16,32,64}, and for parameters ...
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2answers
7k views

How to check whether a process is daemon or not?

I have written a small daemon that starts at the boot time and does all the things perfectly like writing in the log file. But I want to know, how can we check whether that process is daemon or not? ...
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1answer
285 views

Linux [admin] How to test pivot_root?

I want to test the pivot_root command line, which moves the root file system of the current process to the directory put_old and makes new_root the new root file system. ...
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1answer
63 views

snd_rawmidi_open() waits forever - no error message

I am trying to use ALSA for MIDI purposes in C. My problem is, snd_rawmidi_open() sort of "crashes" (waits forever like a while loop) when using valuable arguments : #include <stdio.h> ...