Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: System Calls using C w/BASH
Top Forums Programming System Calls using C w/BASH Post 302611681 by whyte_rhyno on Friday 23rd of March 2012 09:26:28 AM
Old 03-23-2012
System Calls using C w/BASH
Hello all,

I'm attempting to write a basic application that appends an arbitrary list of txt files to one txt file.

So, for example, if the application is run like so:

appendFileToFile file1.txt file2.txt file3.txt the system command should, hopefully be, cat [theFiles] >> testfile.txt

I'm using C, then making a call to the system in BASH. However, I keep getting segmentation faults.

My code below:

Code:
#include <stdio.h>
#include <string.h>

int main(int argc, char *argv[])
{
    
    int i;
    char theCommand[] = "cat ";
  
    for (i = 1; i < argc; i++)
    {
        strcat(theCommand, argv[i]);
    }
    strcat(theCommand, " >> testfile.txt");
    system(theCommand);

    return 0;
}

Thanks for you time.
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

System Calls

What does the system call "dup" do? What is the difference between dup and dup2 I have a fair idea of what it does but I am confused when its coming down to the exact details... Please help me!:confused: (2 Replies)
Discussion started by: clickonline1
2 Replies

2. UNIX for Dummies Questions & Answers

System calls for cp and mv

Which system calls are made for operations cp and mv (2 Replies)
Discussion started by: gaurava99
2 Replies

3. UNIX for Dummies Questions & Answers

System calls?

open, creat, read, write, lseek and close Are they all primitive? :confused: *Another Question: is there a different between a system call, and an i/o system call? (2 Replies)
Discussion started by: PlunderBunny
2 Replies

4. Solaris

System calls ?

where can i find the differences in System calls between solaris and aix? also is it possible to find a comprehensive list of them? (1 Reply)
Discussion started by: TECHRAMESH
1 Replies

5. UNIX Desktop Questions & Answers

Using system calls

Hi, I'm new to UNIX system calls. Can someone share your knowledge as to how exactly system calls should be executed? Can they be typed like commands such as mkdir on the terminal itself? Also, are there any websites which will show me an example of the output to expect when a system call like... (1 Reply)
Discussion started by: ilavenil
1 Replies

6. Programming

System calls

why user is not able to switch from user to kernel mode by writing the function whose code is identical to system call. (1 Reply)
Discussion started by: joshighanshyam
1 Replies

7. BSD

system calls

what is the functions and relationship between fork,exec,wait system calls as i am a beginer just want the fundamentals. (1 Reply)
Discussion started by: sangramdas
1 Replies

8. UNIX for Dummies Questions & Answers

About system calls.

Hi all, I am new here . I want to know about system call in detail. As system calls are also function .How system identifies it.:) (2 Replies)
Discussion started by: vishwasrao
2 Replies

9. Shell Programming and Scripting

c++ calls bash

hi, i'm a noob i have a quuestion: is possible to call and run the bash script by c++ program? if so, is it posible in grafic? specially Qt ? thanks (8 Replies)
Discussion started by: 3.14.TR
8 Replies

10. UNIX for Dummies Questions & Answers

system calls in C

Hello, how would i be able to call ps in C programming? thanks, ---------- Post updated at 01:39 AM ---------- Previous update was at 01:31 AM ---------- here's the complete system call, ps -o pid -p %d, getpit() (2 Replies)
Discussion started by: l flipboi l
2 Replies

LEARN ABOUT REDHAT

unix2dos

unix2dos(1)						      General Commands Manual						       unix2dos(1)

NAME

       unix2dos - UNIX to DOS text file format converter

SYNOPSYS

       unix2dos [options] [-c convmode] [-o file ...] [-n infile outfile ...]

       Options:

       [-hkqV] [--help] [--keepdate] [--quiet] [--version]

DESCRIPTION

       This manual page documents unix2dos, the program that converts text files in UNIX format to DOS format.

OPTIONS

       The following options are available:

       -h --help
	      Print online help.

       -k --keepdate
	      Keep the date stamp of output file same as input file.

       -q --quiet
	      Quiet mode. Suppress all warning and messages.

       -V --version
	      Prints version information.

       -c --convmode convmode
	      Sets conversion mode. Simulates unix2dos under SunOS.

       -o --oldfile file ...
	      Old file mode. Convert the file and write output to it. The program default to run in this mode. Wildcard names may be used.

       -n --newfile infile outfile ...
	      New  file  mode.	Convert the infile and write output to outfile. File names must be given in pairs and wildcard names should NOT be
	      used or you WILL lost your files.

EXAMPLES

       Get input from stdin and write output to stdout.

	      unix2dos

       Convert and replace a.txt. Convert and replace b.txt.

	      unix2dos a.txt b.txt

	      unix2dos -o a.txt b.txt

       Convert and replace a.txt in ASCII conversion mode.  Convert and replace b.txt in ISO conversion mode.

	      unix2dos a.txt -c iso b.txt

	      unix2dos -c ascii a.txt -c iso b.txt

       Convert and replace a.txt while keeping original date stamp.

	      unix2dos -k a.txt

	      unix2dos -k -o a.txt

       Convert a.txt and write to e.txt.

	      unix2dos -n a.txt e.txt

       Convert a.txt and write to e.txt, keep date stamp of e.txt same as a.txt.

	      unix2dos -k -n a.txt e.txt

       Convert and replace a.txt. Convert b.txt and write to e.txt.

	      unix2dos a.txt -n b.txt e.txt

	      unix2dos -o a.txt -n b.txt e.txt

       Convert c.txt and write to e.txt. Convert and replace a.txt.  Convert and replace b.txt. Convert d.txt and write to f.txt.

	      unix2dos -n c.txt e.txt -o a.txt b.txt -n d.txt f.txt

DIAGNOSTICS

BUGS

       The program does not work properly under MSDOS in stdio processing mode.  If you know why is that so, please tell me.

AUTHOR

       Benjamin Lin - ( blin@socs.uts.edu.au )

MISCELLANY

       Tested environment:

	      Linux 1.2.0 with GNU C 2.5.8

	      SunOS 4.1.3 with GNU C 2.6.3

	      MS-DOS 6.20 with Borland C++ 4.02

       Suggestions and bug reports are welcome.

SEE ALSO

       dos2unix(1)

1995.03.31							   unix2dos v2.2						       unix2dos(1)
All times are GMT -4. The time now is 12:15 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy