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The standard error stream


#include <stdio.h>

FILE * stderr;


This global variable defines the standard error stream. It's set to the console by default, but you can redirect it by calling freopen().

STDERR_FILENO, which is defined in <unistd.h>, defines the file descriptor that corresponds to stderr.


ANSI, POSIX 1003.1

See also:

assert(), err(), errx(), getopt(), herror(), perror(), stdin, stdout, strerror(), verr(), verrx(), vwarn(), vwarnx(), warn(), warnx()