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-rw-r--r--manual/examples/argp-ex2.c21
1 files changed, 20 insertions, 1 deletions
diff --git a/manual/examples/argp-ex2.c b/manual/examples/argp-ex2.c
index d1b149b494..55f59f2ab8 100644
--- a/manual/examples/argp-ex2.c
+++ b/manual/examples/argp-ex2.c
@@ -1,11 +1,30 @@
 /* Argp example #2 -- a pretty minimal program using argp */
 
+/* This program doesn't use any options or arguments, but uses
+   argp to be compliant with the GNU standard command line
+   format.
+
+   In addition to making sure no arguments are given, and
+   implementing a --help option, this example will have a
+   --version option, and will put the given documentation string
+   and bug address in the --help output, as per GNU standards.
+
+   The variable ARGP contains the argument parser specification;
+   adding fields to this structure is the way most parameters are
+   passed to argp_parse (the first three fields are usually used,
+   but not in this small program).  There are also two global
+   variables that argp knows about defined here,
+   ARGP_PROGRAM_VERSION and ARGP_PROGRAM_BUG_ADDRESS (they are
+   global variables becuase they will almost always be constant
+   for a given program, even if it uses different argument
+   parsers for various tasks).  */
+
 #include <argp.h>
 
 const char *argp_program_version =
   "argp-ex2 1.0";
 const char *argp_program_bug_address =
-  "<bug-gnu-utils@@prep.ai.mit.edu>";
+  "<bug-gnu-utils@@gnu.org>";
 
 /* Program documentation.  */
 static char doc[] =