NAME

perror, syslog − system error messages

SYNOPSIS

­#include <u.h>
­#include <libc.h>

void perror(char ∗s)

void syslog(int cons, char ∗logname, char ∗fmt, ...) 

DESCRIPTION

­Perror produces a short error message on the standard error file describing the last error encountered during a call to the system.  First the argument string ­s is printed, then a colon, then the message and a newline.  If ­s is 0, only the error message and newline are printed. 

­Syslog logs messages in the file named by ­logname in the directory /sys/log; the file must already exist and should be append-only.  ­Logname must contain no slashes.  The message is a line with several fields: the name of the machine writing the message; the date and time; the message specified by the print(2) format ­fmt and any following arguments; and a final newline.  If ­cons is set or the log file cannot be opened, the message is also printed on the system console.  ­Syslog can be used safely in multi-threaded programs. 

SOURCE

­/sys/src/libc/port/perror.c
­/sys/src/libc/9sys/syslog.c

SEE ALSO

intro(2), errstr(2), the ­%r format in print(2)

BUGS

­Perror is a holdover; the ­%r format in print(2) is preferred.

Plan 9  —  April 04, 1995