Add license & descriptive headerHEADmaster

1 files changed, 29 insertions, 0 deletions

diff --git a/m4env.c b/m4env.c
index 0838e86..de98f9c 100644
--- a/m4env.c
+++ b/m4env.c
@@ -1,3 +1,32 @@
+/*
+ * NAME
+ *     m4env - run m4 with environment variables accessible as macros
+ *
+ * SYNOPSIS
+ *     m4env [OPTIONS] [FILES]
+ *
+ * DESCRIPTION
+ *     Modifies the command line by replacing argv[0] with "m4" and
+ *     inserting a "-D" option for each environment variable before
+ *     the original argv[1].  Then execs m4 (from the PATH) with
+ *     the created command line.
+ *
+ *     As a result, each environment variable is available for expansion
+ *     as a m4 macro with the same name.
+ *
+ *     E.g,
+ *
+ *        echo "Your user name is LOGNAME" | m4env
+ *
+ * AUTHOR
+ *     Sergey Poznyakoff
+ *
+ * LICENSE
+ *     "THE BEER-WARE LICENSE" (Revision 42):
+ *     <gray@gnu.org> wrote this file.  As long as you retain this notice you
+ *     can do whatever you want with this stuff. If we meet some day, and you
+ *     think this stuff is worth it, you can buy me a beer in return.
+ */
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>