PERROR(3)	    UNIX Programmer's Manual		PERROR(3)



NAME
     perror, strerror - system error messages

SYNOPSIS
     perror(s)
     char *s;

     #include <string.h>

     _c_h_a_r *
     strerror(errnum)
     int errnum;

DESCRIPTION
     The strerror() and perror() functions look up the error mes-
     sage string corresponding to an error number.

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

     The perror() function finds the error message corresponding
     to the current value of the global variable _e_r_r_n_o (intro(2))
     and writes it, followed by a newline, to the standard error
     file descriptor.  If the argument _s_t_r_i_n_g is non-NULL, it is
     prepended to the message string and separated from it by a
     colon and space (`: ').  If _s_t_r_i_n_g is NULL, only the error
     message string is printed.

     If _e_r_r_n_u_m is not a recognized error number, the error mes-
     sage string will contain ``Unknown error: '' followed by the
     error number in decimal.

     The error messages are stored in a data file now rather than
     an in memory array.  See syserror(5).

SEE ALSO
     mkerrlst(1), intro(2), psignal(3), strerror(3), syserror(3),
     syserror(5)

BUGS
     The strerror() function returns its result in a static
     buffer which may be overwritten by subsequent calls.

     The array sys_errlist[] and the global sys_nerr are obsolete
     and should not be used.  They have, for the time being, been
     placed in an object library liberrlst.a.








Printed 11/26/99	 March 21, 1996                         1