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



      NAME
           perror, sys_errlist, sys_nerr - system error messages

      SYNOPSIS
           perror(s)
           char *s;

           int sys_nerr;
           char *sys_errlist[];

      DESCRIPTION
           Perror produces a short error message on  the  standard  error  file
           describing  the  last  error encountered during a call to the system
           from a C program.  First the argument string s is  printed,  then  a
           colon, then the message and a new-line.  Most usefully, the argument
           string is the name of the program which  incurred  the  error.   The
           error  number  is  taken  from  the  external  variable  errno  (see
           intro(2)), which is set when errors occur but not cleared when  non-
           erroneous calls are made.

           To simplify variant formatting of messages, the  vector  of  message
           strings  sys_errlist  is  provided; errno can be used as an index in
           this table to get the message string without the newline.   Sys_nerr
           is  the  number  of messages provided for in the table; it should be
           checked because new error codes may be added to  the  system  before
           they are added to the table.

      SEE ALSO
           intro(2)


























      Printed 11/16/83                                                        1