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Full Discussion: fork() and dup()
Top Forums Programming fork() and dup() Post 31753 by AkumaTay on Wednesday 13th of November 2002 02:25:07 AM
Old 11-13-2002
fork() and dup()

I have met this code:

switch(fork()) {

case 0:
close(1);
dup(p[1]);
close(p[0]);
close(p[1]);
execvp(<whatever>);
perror("Exec failed");
}

Can anyone tell me what this piece of code does?
Thx alot..
 

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explain_close_or_die(3) 				     Library Functions Manual					   explain_close_or_die(3)

NAME
explain_close_or_die - close a file descriptor and report errors SYNOPSIS
#include <libexplain/close.h> void explain_close_or_die(int fildes); DESCRIPTION
The explain_close_or_die function is used to call the close(2) system call. On failure an explanation will be printed to stderr, obtained from explain_close(3), and then the process terminates by calling exit(EXIT_FAILURE). This function is intended to be used in a fashion similar to the following example: explain_close_or_die(fildes); fildes The fildes, exactly as to be passed to the close(2) system call. Returns: This function only returns on success. On failure, prints an explanation and exits. SEE ALSO
close(2) close a file descriptor explain_close(3) explain close(2) errors exit(2) terminate the calling process COPYRIGHT
libexplain version 0.52 Copyright (C) 2008 Peter Miller explain_close_or_die(3)
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