PERROR(3)                                                            PERROR(3)



NAME
       perror, sys_errlist, sys_nerr - system error messages

SYNOPSIS
       perror(s)
       char *s;

       int sys_nerr;
       char *sys_errlist[];

DESCRIPTION
       _P_e_r_r_o_r  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 _e_r_r_n_o (see  _i_n_t_r_o(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 _s_y_s__e_r_r_l_i_s_t is provided; _e_r_r_n_o can be used as an index in  this
       table  to  get the message string without the newline.  _S_y_s__n_e_r_r 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)



4th Berkeley Distribution        May 15, 1985                        PERROR(3)