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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1answer
146 views

Error: Missing newline before EOF - inserted

In my application I am inserting some files in main file. In that there is common header file to all the code files (*.c). This giving me error: D:\New folder\COM_Port_Cont\COM_Port_Task.h(268) : ...
18
votes
6answers
6k views

What C library version does my system use?

How can I tell for sure what userland C library my system uses? Possible reasons to need this information include: There's a gigantic source package I am considering downloading which I'm sure will ...
0
votes
1answer
140 views

libext2fs gcc linking error

I am writing a C program which uses libext2fs: #include <ext2fs/ext2fs.h> int main(int argc, char *argv[]) { char *fsname = argv[1]; errcode_t err; ext2_filsys fs; err= ...
5
votes
3answers
397 views

Are there “esoteric” (weird) but standards-compliant C compilers or runtimes?

As we know, the C standard does not specify a lot of details of the implementation, for example value of NULL pointer, order of bits and bytes (endiannes), alignment in structs and of stack ...
0
votes
1answer
132 views

Compile OS with gcc and ld on Linux

I'm practicing operating system development and am having trouble getting gcc and ld to produce pure binary without any metadata or section labels. For example: int function(){ return 100;} would ...
1
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0answers
204 views

How to cause memory fragmentation on a Linux based embedded device?

Hardware ARM What am I trying to do: Answer: I am trying to create memory fragmentation on a Linux 2.6.31 based swapless embedded device. Why: Answer:I am trying to port some patches to Linux ...
3
votes
2answers
1k views

Writing own daemon. systemd error: Failed to read PID from file: Invalid argument

I'm trying to write own daemon a la very simple MPD (it's operating systems laboratory work). I made it work: it starts like a daemon (output of ps): 1 14877 14877 14877 ? -1 Ss 0 ...
2
votes
1answer
130 views

Can you use LXC through C?

I want to use LXC to 'container' plugins my application is loading. Am I able to do this through C? I have been Googling a lot about it, but there don't seem to be any headers, only scripts that can ...
3
votes
1answer
629 views

How to let a user execute a script owned by root? Setuid doesn't seem to work anymore [duplicate]

I have some bash scripts that I use with the user 'root' to manage iptable rules. The problem is that I want these things at the same time: The script must be owned by root Permissions must be 700 ...
-2
votes
1answer
91 views

How to compile c, c++ and python code as “Released/Final” version? [closed]

I want to know if there are ways to compile C, C++ and Python code in order to not be able to reverse engineering it over Linux or not? I have heard there are some ways over Windows to do it, but I ...
9
votes
7answers
2k views

Possible to find out the sizes of data types (int, float, double, …) on a system, without writing a C program?

Is it possible to find out the sizes of data types (int, float, double, ...) on a Linux system, without writing a C program? Would the results for C same as for C++, and other programming languages ...
2
votes
0answers
210 views

How can I compile minix when I make changes in libraries

I am looking for a way to compile minix. The make hdboot command seems to do nothing with the directories under /usr/src/lib. I changed only one .c file in syslib. Do I have to do make world for this ...
0
votes
3answers
122 views

In makefile when do we use .o files?

In the following make file, what is the significance of adding .o files instead of .c files? CC=gcc CFLAGS=-I. hellomake: hellomake.o hellofunc.o $(CC) -o hellomake hellomake.o hellofunc.o ...
5
votes
2answers
345 views

What would I get when sudo a kernel-destructive program?

It suddenly comes to me how easy it will be for a sudoer to crash the kernel, so I tried something like this: #include<stdio.h> int main(){ printf("hello world"); int a; ...
3
votes
1answer
1k views

Error compiling FTDI VCP drivers: Cannot find version.h

driver installation fails of FTDI VCP driver during make install. Running ElementaryOS with kernel 3.11.0-14-generic make install awk: cannot open ...
2
votes
0answers
230 views

Writing to Arbitrary Memory Addresses [closed]

I'm reading "Art of Exploitation 2nd Ed." and I have a question regarding a section on format string attacks. Target program Below code (fmt_vuln.c) is a target program. #include <stdio.h> ...
1
vote
3answers
135 views

Is there any manual about C in Linux? If any, what is it?

While I find that we can read some manuals about Library calls (C library functions) & acsii in Linux. But I still do not find any manual about C precedence order so far. So you can recommend ...
2
votes
2answers
436 views

How to make processes not die after its parent dies?

I've been messing with forkbombs and noticed that if I just fork() processes repeatedly, killing the initial process will bring down the whole tree. This is not the case for forkbombs written in BASH ...
3
votes
2answers
109 views

How to write software to compile with external libraries?

I want to code open source software with dependencies. I have skills in C/C++ and a minimum makefile knowledge. But im curious about coding this like ./configure && make stuff and how to ...
3
votes
1answer
2k views

Start 4 programs on startup in Linux Mint via terminal

I'm working on a project and I hope you can help me solve a problem. I have four programs that are written in C. They have been compiled using gcc and they work as they should. Because the four ...
0
votes
1answer
106 views

C-library HMAC_MD5 questions

We are working with an older software product that has some limited programming capabilities - specifically, no bit manipulation functions. This has created a significant problem as we need to ...
0
votes
1answer
203 views

Read and parse XML input via TCP [closed]

I'm setting up something where I'll need to be able to setup a service that accepts input on a TCP port and then parses the XML provided and extracts the necessary data, then posts that to Google's ...
5
votes
1answer
566 views

command substitution handling in fish vs. other shells (sh, bash, zsh)

The program mc (Midnight Commander) is not intended to be used for command substitution, but I would like to know why different shells behave differently when this program (and it seems like other ...
3
votes
2answers
806 views

Why does Linux have a C compiler by default?

Why does a Linux distribution have gcc installed in advance? Is it because most of the applications in linux are written in C? What would happen if the gcc directory is deleted?
1
vote
1answer
190 views

Parsing protocol and url from packet payload

We are using pf_ring to capture packets. We are able to decipher information like source and destination ip, mac etc from the header information. Now we are moving into payload to decide the type of ...
3
votes
0answers
158 views

Fork vs. thread system time [closed]

I got the following logs: Program 1: Taken from a program executed 64 fork calls: real 0m0.023s user 0m0.068s sys 0m0.008s Program 2: Taken from a program executed 64 thread calls: real 0m0.613s ...
2
votes
1answer
329 views

Dependencies problem with automake

I am using automake on Debian Squeeze for compiling a very simple C project with 6 source files. The issue comes when I try to compile the sources using the generated Makefile. One of the sources ...
10
votes
2answers
230 views

Is there a way to mirror USB outputs?

I'm currently writing a program for a project. It is for a braille reading system where I have a braille display connected via USB that is controlled by a program called brltty. One of the ...
1
vote
1answer
246 views

How to trace process scheduling of certain process?

For a project at my university I am researching ways to trace, log and manipulate the process scheduling of certain processes. I would like to launch an number of applications, everyone in a single ...
4
votes
4answers
902 views

Is it possible to make multi-level directory? [duplicate]

Using mkdir() (the C function) I can create a 1-level directory, if I want to create multi_level directory like: folder/subfolder/subsubfolder is it possible? if so, how?
5
votes
1answer
340 views

Effect of static and dynamic linking on start address

I have a simple C program. I run: $ gcc Q1.c -Wall -save-temps -o Q1 Then I inspect the executable generated: $ objdump -f Q1 Q1: file format elf32-i386 architecture: i386, flags 0x00000112: ...
4
votes
3answers
880 views

default wordsize in UNIX/Linux

I was inspecting the preprocessed output of my C program and happened to look at the header file wordsize.h It is located in /usr/include/i386-linux-gnu/bits/wordsize.h the file contains only one ...
4
votes
1answer
127 views

Portions of the file Header

I was working through my C programs, I am new to Linux/UNIX development and was having a look around. I created a simple C program of Hello world and was inspecting the compilation process. I tried ...
1
vote
4answers
2k views

I can not get my Realtek 8723 driver source compiled

I have a Lenovo IdeaPad Yoga 13. WLAN won't work out of box with fedora 18. So I googled around and found this 2 links: ...
-3
votes
2answers
357 views

Using file system call

I'm trying to learn system calls for open,write and close a file. I use this sample and the result is: gcc: error trying to exec 'cc1plus': execvp: No such file or directory Here's my program: ...
0
votes
1answer
277 views

Understanding a XINU system call - getstk.c [closed]

I am having trouble conceptually understanding what is going on towards the end of this system call, and why. I understand the getstk.c method returns the highest memory address of available space, ...
2
votes
2answers
331 views

Why read() is slower than getc()? [closed]

Why is read slower than getc? For example, this: for (;;) { chr++; amr=read(file1, &wc1, 1); amr2=read(file2, &wc2, 1); if (wc1 == wc2) { if ...
1
vote
2answers
395 views

Monitoring script started by rc.local

We have a C program which is started using rc.local´. We added a line like this: /usr/local/bin/pc to the rc.local file. pc is a compiled C program. Everything is working fine at the moment. What ...
0
votes
1answer
418 views

USB-Serial Driver(Exar Xr21v1414) Run Error

I'm currently trying to run the bellow driver in linux-3.8.3 on Exar xr21v1414 http://www.exar.com/connectivity/uart-and-bridging-solutions/usb-uarts/xr21v1410, but when i install the driver ...
1
vote
1answer
317 views

How to explicitly load shell interpreter in a C program

I want to create an executable script which is not readable/writable However since an interpreter needs to read this file it is not possible to do so directly. Therefore I wanted to know if I could ...
0
votes
1answer
77 views

Can a GTK applet widget be instantiated through dbus?

I just posted this: #274616: “Simple” gnome applets in Unity - stickynotes ... where I could instantiate a Gnome 2 bonobo applet in a standalone window, ... using ...
-1
votes
2answers
116 views

Why rsh not opens and reads PAM modules and limits.conf?

I am working on a project, that uses rsh utility for remote connection. But my project needs some extra features for that, so I add that features. Till now, all the things are going fine. But when I ...
3
votes
1answer
249 views

Make Completion Progress Script

Any time I'm executing a build process that takes several hours, I inevitably stare at my terminal and wonder, "how much longer?" Sometimes, I manually pick up on some pathname echoed to the terminal ...
-1
votes
3answers
576 views

telnet implementation using C [closed]

The program in general is I want to implement telnet program. On the client side user send its logging name and password, and if it is correct he starts to send commands to the server On the Server ...
0
votes
2answers
189 views

Which process updates /proc/scsi/scsi?

I wrote C that displays info about my hardware on ubuntu. Now I wonder how I can make it more flexible such as querying the hardware directly instead of the file the os updates. So I think I can look ...
1
vote
0answers
245 views

mod_rewrite: undefined symbol: lstat error

I compiled the mod rewrite for apache (version 1.3.0) however, when I try to run the server I have this error about mod_rewrite: Syntax error on line 27 of /home/myuser/apache/etc/httpd.conf: Cannot ...
3
votes
1answer
871 views

Send log messages to a different location

I want to send messages from C program and from Perl script to a file (for example, /var/log/my_log). I don't have access to the syslog daemon configuration, so I think in launch a differente syslog ...
-3
votes
2answers
89 views

Which Linux distro/mode offers lowest interference when running your own applications?

I'm interested in a Linux distro to build C projects and test their behavior in a very predictable and controlled environment. I'm especially concerned about letting the scheduler deal as much as ...
0
votes
1answer
159 views

Having trouble executing a compiled C program

I am running an Ubuntu v10.04 through VirtualBox. To test the persistence of files I create in the virtual machine, I wrote a very basic C program. When I shutdown the virtual machine and restart it, ...
2
votes
3answers
428 views

Linux GCC compiler options

I have recently started using Linux as a tool for programing. In my book, I have seen that the GCC is used with 2 options: -g and -o. Now, I know that -o is to set a filename, but what is the purpose ...