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sys_errlist (3)

>> sys_errlist (3) ( FreeBSD man: Библиотечные вызовы )

sys_errlist (3) ( Linux man: Библиотечные вызовы )

BSD mandoc

NAME



perror

 
strerror

 
strerror_r

 
sys_errlist

 
sys_nerr

 - system error messages

LIBRARY

Lb libc

SYNOPSIS

#include <stdio.h>
void perror (const char *string);
Vt extern const char * const sys_errlist[] ; Vt extern const int sys_nerr ; #include <string.h>
char * strerror (int errnum);
int strerror_r (int errnum char *strerrbuf size_t buflen);

DESCRIPTION

The strerror (,);
strerror_r ();
and perror ();
functions look up the error message string corresponding to an error number.

The strerror ();
function accepts an error number argument Fa errnum and returns a pointer to the corresponding message string.

The strerror_r ();
function renders the same result into Fa strerrbuf for a maximum of Fa buflen characters and returns 0 upon success.

The perror ();
function finds the error message corresponding to the current value of the global variable errno (intro(2) ) and writes it, followed by a newline, to the standard error file descriptor. If the argument Fa string is non- NULL and does not point to the null character, this string is prepended to the message string and separated from it by a colon and space (``: '' ) otherwise, only the error message string is printed.

If the error number is not recognized, these functions return an error message string containing ``Unknown error: '' followed by the error number in decimal. The strerror ();
and strerror_r ();
functions return Er EINVAL as a warning. Error numbers recognized by this implementation fall in the range 0 < Fa errnum < Fa sys_nerr .

If insufficient storage is provided in Fa strerrbuf (as specified in Fa buflen ) to contain the error string, strerror_r ();
returns Er ERANGE and Fa strerrbuf will contain an error message that has been truncated and NUL terminated to fit the length specified by Fa buflen .

The message strings can be accessed directly using the external array sys_errlist The external value sys_nerr contains a count of the messages in sys_errlist The use of these variables is deprecated; strerror ();
or strerror_r ();
should be used instead.

STANDARDS

The perror ();
and strerror ();
functions conform to St -isoC-99 . The strerror_r ();
function conforms to St -p1003.1-2001 .

HISTORY

The strerror ();
and perror ();
functions first appeared in BSD 4.4 The strerror_r ();
function was implemented in Fx 4.4 by An Wes Peters Aq [email protected] .