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perror
—print an error message on standard errorSynopsis
#include <stdio.h> void perror(char *prefix); void _perror_r(struct _reent *reent, char *prefix);
Description
Use perror
to print (on standard error) an error message
corresponding to the current value of the global variable errno
.
Unless you use NULL
as the value of the argument prefix, the
error message will begin with the string at prefix, followed by a
colon and a space (:
). The remainder of the error message is one
of the strings described for strerror
.
The alternate function _perror_r
is a reentrant version. The
extra argument reent is a pointer to a reentrancy structure.
Returns
perror
returns no result.
Portability
ANSI C requires perror
, but the strings issued vary from one
implementation to another.
Supporting OS subroutines required: close
, fstat
, isatty
,
lseek
, read
, sbrk
, write
.