Apache::SIG - Override apache signal handlers with Perl's

SYNOPSIS

        PerlFixupHandler Apache::SIG

DESCRIPTION

       When a client drops a connection and apache is in the mid-
       dle of a write, a timeout will occur and httpd sends a
       SIGPIPE.  When apache's SIGPIPE handler is used, Perl may
       be left in the middle of it's eval context, causing
       bizarre errors during subsequent requests are handled by
       that child.  When Apache::SIG is used, it installs a dif-
       ferent SIGPIPE handler which rewinds the context to make
       sure Perl is back to normal state, preventing these
       bizarre errors.

       If you would like to log when a request was cancelled by a
       SIGPIPE in your Apache access_log, you can declare
       Apache::SIG as a handler (any Perl*Handler will do, as
       long as it is run before PerlHandler, e.g. PerlFixupHan-
       dler), and you must also define a custom LogFormat in your
       httpd.conf, like so:

       PerlFixupHandler Apache::SIG LogFormat "%h %l %u %t \"%r\"
       %s %b %{SIGPIPE}e"

       If the server has noticed that the request was cancelled
       via a SIGPIPE, then the log line will end with `1', other-
       wise it will just be a dash.

CAVEATS

       The signal handler in this package uses the subprocess_env
       table of the main request object to supply the 'SIGPIPE'
       "environment variable" to the log handler. If you already
       use the key 'SIGPIPE' in your subprocess_env table, then
       you can redefine the key like this:

       $Apache::SIG::PipeKey = 'my_SIGPIPE';

       and log it like this:

       LogFormat "%h %l %u %t \"%r\" %s %b %{my_SIGPIPE}e"

AUTHORS

       Doug MacEachern and Doug Bagley

SEE ALSO

       perlvar(1)