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Full Discussion: dup()
Top Forums Programming dup() Post 9584 by vinchen on Tuesday 30th of October 2001 11:22:45 AM
Old 10-30-2001
Data dup()

Would anyone be so kind to explain to me the function of dup() in UNIX? As far as I am concerned, it duplicates a file descriptor. Under what circumstances would we need to duplicate a file descriptor in a UNIX environment?

Thank you.

vinchen
 

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explain_dup_or_die(3)					     Library Functions Manual					     explain_dup_or_die(3)

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