لطفا منتظر باشید ...
Recipe 9.33 Writing Log Entries via Perl
9.33.1 Problem
You want
to add information to the system log from a Perl program.
9.33.2 Solution
Use the Perl
module
Sys::Syslog, which implements the API described
in the sidebar, The syslog API.
syslog-demo.pl
#!/usr/bin/perl
use Sys::Syslog qw(:DEFAULT setlogsock);
use File::Basename;
my $count = 0;
my $host = "some-machine ";
setlogsock("unix");
openlog(basename($0), "pid", "local3");
syslog("warning", "%d connections from %s", $count, $host);
syslog("authpriv|err", "intruder alert!");
syslog("err", "can't open configuration file: %m");
closelog( );
9.33.3 Discussion
The system logger by default refuses to accept
network
connections (assuming you have not used the syslogd
-r option). Unfortunately, the Perl module uses network
connections by default, so our recipe calls
setlogsock to force the use of a local
socket instead. If your syslog messages seem to
be disappearing into thin air, be sure to use
setlogsock. Recent versions of
Sys::Syslog resort to a local socket if the
network connection fails, but use of setlogsock
for reliable operation is a good idea, since the local socket should
always work. Note that setlogsock must be
explicitly imported.Perl scripts can pass the %m
format specifier to
syslog to include system error messages, as an
alternative to interpolating the $! variable. Be
sure to use %m (or $!) only
when a system error has occurred, to avoid misleading messages.
9.33.4 See Also
Sys::Syslog(3pm), syslog(3).
