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# 1  
Old 11-17-2008
two questions

hey all, I have question when am writing simple shell...

in the child am calling execvp, i want the parent to know when execvp returns - 1. how can i let the parent know the result of execvp

thanks in advance
# 2  
Old 11-17-2008
Moved to High Level Programming.
If it's really shell and not C, let me know and I will move the threat back to Shell Programming.
# 3  
Old 11-17-2008
The code is being wrriten in c.
# 4  
Old 11-17-2008
so this is the right forum.
# 5  
Old 11-17-2008
call waitpid() in the parent using the pid of the child. Call exit(-1) from the child.
There are macros in sys/wait.h like WIFEXITED() that you use to evaluate the return status code from the child in the parent.

Is that what you mean? See Johnson & Troan 'Linux Application Development' They develop a shell step-by-step. See the ladsh1.c examples here:
Linux Application Development: Source Code
# 6  
Old 11-17-2008

Last edited by joey; 11-18-2008 at 08:06 AM..
# 7  
Old 11-17-2008
Did you:
#include <sys/types.h>
#include <sys/wait.h>

...at the top of your code? waitpid needs both.
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