DOC: add description of pidfile in master-worker mode
Previously, pidfile was only described for daemon mode. In the case of
master-worker mode, the handling of pidfile is different from daemon mode,
so the description has been added.
diff --git a/doc/haproxy.1 b/doc/haproxy.1
index 7554f9d..4c2d786 100644
--- a/doc/haproxy.1
+++ b/doc/haproxy.1
@@ -105,7 +105,8 @@
.TP
\fB\-p <pidfile>\fP
Ask the process to write down each of its children's pids to this file
-in daemon mode.
+in daemon mode or ask the process to write down its master's pid to
+this file in master-worker mode.
.TP
\fB\-dk\fP