From 50ec5c074ab23fe0fc67915a7c3208faaf8d61d7 Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Wed, 26 Jun 1996 19:20:33 +0000
Subject: [PATCH] Add flock; warn about lockdata system dependency when using
 fcntl.

---
 Doc/lib/libfcntl.tex | 10 +++++++++-
 Doc/libfcntl.tex     | 10 +++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/Doc/lib/libfcntl.tex b/Doc/lib/libfcntl.tex
index 8539e2aa435..1aba52095e7 100644
--- a/Doc/lib/libfcntl.tex
+++ b/Doc/lib/libfcntl.tex
@@ -36,6 +36,12 @@ The module defines the following functions:
   \code{IOCTL}.
 \end{funcdesc}
 
+\begin{funcdesc}{flock}{fd\, op}
+Perform the lock operation \var{op} on file descriptor \var{fd}.
+See the Unix manual for details.  (On some systems, this function is
+emulated using \code{fcntl}.)
+\end{funcdesc}
+
 If the library modules \code{FCNTL} or \code{IOCTL} are missing, you
 can find the opcodes in the C include files \code{sys/fcntl} and
 \code{sys/ioctl}. You can create the modules yourself with the h2py
@@ -57,4 +63,6 @@ rv = fcntl(file.fileno(), FCNTL.F_SETLKW, lockdata)
 
 Note that in the first example the return value variable \code{rv} will
 hold an integer value; in the second example it will hold a string
-value.
+value.  The structure lay-out for the \var{lockadata} variable is
+system dependent -- therefore using the \code{flock()} call may be
+better.
diff --git a/Doc/libfcntl.tex b/Doc/libfcntl.tex
index 8539e2aa435..1aba52095e7 100644
--- a/Doc/libfcntl.tex
+++ b/Doc/libfcntl.tex
@@ -36,6 +36,12 @@ The module defines the following functions:
   \code{IOCTL}.
 \end{funcdesc}
 
+\begin{funcdesc}{flock}{fd\, op}
+Perform the lock operation \var{op} on file descriptor \var{fd}.
+See the Unix manual for details.  (On some systems, this function is
+emulated using \code{fcntl}.)
+\end{funcdesc}
+
 If the library modules \code{FCNTL} or \code{IOCTL} are missing, you
 can find the opcodes in the C include files \code{sys/fcntl} and
 \code{sys/ioctl}. You can create the modules yourself with the h2py
@@ -57,4 +63,6 @@ rv = fcntl(file.fileno(), FCNTL.F_SETLKW, lockdata)
 
 Note that in the first example the return value variable \code{rv} will
 hold an integer value; in the second example it will hold a string
-value.
+value.  The structure lay-out for the \var{lockadata} variable is
+system dependent -- therefore using the \code{flock()} call may be
+better.