newlib-cygwin/newlib/libc/stdio/perror.c

84 lines
1.7 KiB
C

/*
FUNCTION
<<perror>>---print an error message on standard error
INDEX
perror
INDEX
_perror_r
ANSI_SYNOPSIS
#include <stdio.h>
void perror(char *<[prefix]>);
void _perror_r(void *<[reent]>, char *<[prefix]>);
TRAD_SYNOPSIS
#include <stdio.h>
void perror(<[prefix]>)
char *<[prefix]>;
void _perror_r(<[reent]>, <[prefix]>)
char *<[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>>.
*/
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include "local.h"
void
_DEFUN (_perror_r, (ptr, s),
struct _reent *ptr _AND
_CONST char *s)
{
char *error;
_REENT_SMALL_CHECK_INIT(_stderr_r (ptr));
if (s != NULL && *s != '\0')
{
fputs (s, _stderr_r (ptr));
fputs (": ", _stderr_r (ptr));
}
if ((error = strerror (ptr->_errno)) != NULL)
fputs (error, _stderr_r (ptr));
fputc ('\n', _stderr_r (ptr));
}
#ifndef _REENT_ONLY
void
_DEFUN (perror, (s),
_CONST char *s)
{
_perror_r (_REENT, s);
}
#endif