Using C language to use system calls


 
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Homework and Emergencies Homework & Coursework Questions Using C language to use system calls
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Old 11-22-2012
Quote:
Originally Posted by femchi
Code:
execl("/usr/bin/find","find . -maxdepth 1 -perm 644",(char *)NULL);

it doesnt work properly. do you know what is the problem?
Like they said, it's not a shell, it doesn't split for you.

Also, if it did work, your program would immediately quit, because execl doesn't launch a new program -- it replaces your current program. If you want to create a new process, you have to fork first, then exec. Watch the return value of fork carefully. It creates a clone of your process, and its return value is the only thing which tells them which is which. You have to make sure your child process only does what the child should be doing and not anything else, make sure it quits if exec doesn't work and such.
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