[groff] 04/09: [eqn]: Describe command if asked for `--help`.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 3751207624e0e681da2dd34d1ca41c04128d67de
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Tue Dec 3 15:22:26 2024 -0600

    [eqn]: Describe command if asked for `--help`.
    
    * src/preproc/eqn/main.cpp (usage): If asked for `--help`, summarize
      command purpose in message.
---
 ChangeLog                | 5 +++++
 src/preproc/eqn/main.cpp | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index a2dc01004..44ecfd6af 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2024-12-03  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * src/preproc/eqn/main.cpp (usage): If asked for `--help`,
+       summarize command purpose in message.
+
 2024-12-03  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        * src/preproc/tbl/main.cpp (usage): If asked for `--help`,
diff --git a/src/preproc/eqn/main.cpp b/src/preproc/eqn/main.cpp
index 59067a854..56ab03603 100644
--- a/src/preproc/eqn/main.cpp
+++ b/src/preproc/eqn/main.cpp
@@ -322,6 +322,12 @@ void usage(FILE *stream)
     "usage: %s {-v | --version}\n"
     "usage: %s --help\n",
     program_name, program_name, program_name);
+  if (stdout == stream)
+    fputs("\n"
+"GNU eqn is a filter that translates expressions in its own language,\n"
+"embedded in roff(7) input, into mathematical notation typeset by\n"
+"GNU troff(1).  See the eqn(1) manual page.\n",
+         stream);
 }
 
 int main(int argc, char **argv)