strerror(3c) [opensolaris man page]

strerror(3C)						   Standard C Library Functions 					      strerror(3C)

NAME

       strerror, strerror_r - get error message string

SYNOPSIS

       #include <string.h>

       char *strerror(int errnum);

       int strerror_r(int errnum, char *strerrbuf, size_t  buflen);

DESCRIPTION

       The  strerror() function maps the error number in errnum to an error message string, and returns a pointer to that string. It uses the same
       set of error messages as perror(3C). The returned string should not be overwritten.

       The strerror_r() function maps the error number in errnum to anerror message string and returns the string in the buffer pointed to by str-
       errbuf with length buflen.

RETURN VALUES

       Upon successful completion, strerror() returns a pointer to the generated message string. Otherwise, it sets errno and returns a pointer to
       an error message string. It returns the string "Unknown error" if errnum is not a valid error number.

       Upon successful completion, strerror_r() returns 0.  Otherwise it sets errno and returns the value of  errno  to  indicate  the	error.	It
       returns the string "Unknown error" in the buffer pointed to by strerrbuf if errnum is not a valid error number.

ERRORS

       These functions may fail if:

       EINVAL	 The value of errnum is not a valid error number.

       The strerror_r() function may fail if:

       ERANGE	 The buflen argument specifies insufficient storage to contain the generated message string.

USAGE

       Messages returned from these functions are in the native language specified by the LC_MESSAGES locale category. See setlocale(3C).

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       gettext(3C), perror(3C), setlocale(3C), attributes(5), standards(5)

SunOS 5.11							    31 Mar 2005 						      strerror(3C)

STRERROR(3)						   BSD Library Functions Manual 					       STRERROR(3)

NAME

     perror, strerror, strerror_r, sys_errlist, sys_nerr -- system error messages

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <stdio.h>

     void
     perror(const char *s);

     extern const char * const sys_errlist[];
     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 errnum and returns a pointer to the corresponding message string.

     The strerror_r() function renders the same result into strerrbuf for a maximum of 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, fol-
     lowed by a newline, to the standard error file descriptor.  If the argument s 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 EINVAL as a warning.	Error numbers recognized by this implementation
     fall in the range 0 <= errnum < sys_nerr.

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

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

SEE ALSO

     intro(2), psignal(3)

STANDARDS

     The perror() and strerror() functions conform to ISO/IEC 9899:1999 (``ISO C99'').	The strerror_r() function conforms to IEEE Std 1003.1-2001
     (``POSIX.1'').

HISTORY

     The strerror() and perror() functions first appeared in 4.4BSD.  The strerror_r() function was implemented in FreeBSD 4.4 by Wes Peters
     <wes@FreeBSD.org>.

BUGS

     For unknown error numbers, the strerror() function will return its result in a static buffer which may be overwritten by subsequent calls.

     The return type for strerror() is missing a type-qualifier; it should actually be const char *.

     Programs that use the deprecated sys_errlist variable often fail to compile because they declare it inconsistently.

BSD
								 October 12, 2004							       BSD