unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (SunOS-4.1.3)
Page:
Section:
Apropos / Subsearch:
optional field

PERROR(3)                  Library Functions Manual                  PERROR(3)



NAME
       perror, errno - system error messages

SYNOPSIS
       void perror(s)
       char *s;

       #include <&lt;errno.h>&gt;

       int sys_nerr;
       char *sys_errlist[];
       int errno;

DESCRIPTION
       perror()  produces a short error message on the standard error describ-
       ing the last error encountered during a call to  a  system  or  library
       function.   If  s  is  not  a NULL pointer and does not point to a null
       string, the string it points to is printed, followed by a  colon,  fol-
       lowed  by  a  space,  followed by the message and a NEWLINE.  If s is a
       NULL pointer or points to a null string, just the message  is  printed,
       followed  by  a NEWLINE.  To be of most use, the argument string should
       include the name of the program that 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), psignal(3)



                                6 December 1988                      PERROR(3)