Executing Linux commands in C programs--->please help

dennyvm · 01-15-2004, 08:40 AM

Hai--I'm new to Linux programming but I'm familiar with most of the administrative part of Linux..I would like to know about using Linux commands in a C program, and also about how to create a time stamped file and write to it...

Could anyone guide me or tell me about resources which deals with the above in a detailed manner?

Thank you..This is my first post

-->dennyvm

jtshaw · 01-15-2004, 09:14 AM

The command you are looking for is exec. It comes in a variety of forms. Type "man 3 exec" at the command line to read about it. As far as writing files goes, you will want to look into fopen and fprintf. fopen will create a file if you attempt to open a file that doesn't exist already. All files you create should be timestamped to the last time they were written to.

luxitan · 01-15-2004, 09:51 AM

you should check the system command too

jtshaw · 01-15-2004, 10:51 AM

ya, luxitan is right.

System executes a system call and waits for it to complete before moving on. Exec executes a system call and complete replaces the current running process with the new call. If you don't need to wait for the call to finish you can fork and then exec, otherwise using the system call is what you would want to do.

John