allowing pipes with execution in C
i'm having a heck of a time trying to figure out if i can execute a program, say using execl or similar and using a pipe with that.
ex. i want to print the file size of /home/foo/foo.txt by running
ls -al /home/foo/foo.txt|gawk '{print $5}'
how would i go about doing this? is it even possible? (duh, of course it is... somehow).
Keeping mind that pipes and redirects are a function of the shell, here are a couple of things to try:
1) Use system() to execute the command.
2) If you must use execl(), exec the shell (/bin/bash, /bin/ksh, etc) and pass your command as the sole argument.
3) Put you command in a shell script which you can call from execl().
Jason Deckard
There are far more efficient ways of getting the file size.
But for pipes, you need to look up the pipe system call, and arrange for a pipe to exist between two child processes.
There are far more efficient ways of getting the file size.klausiCode:unsigned long sizeoffile(FILE *file) { fseek(file,0,SEEK_END); return(ftell(file)); }
When I close my eyes nobody can see me...
