master c4fcf2f: Fsubstitute_in_file_name doc string clarification

[Lars Ingebrigtsen]

branch: master
commit c4fcf2fc6fbdddb1da2ec1166bf95bfb72baff1a
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Fsubstitute_in_file_name doc string clarification
    
    * src/fileio.c (Fsubstitute_in_file_name): Mention that undefined
    variables aren't replaced (as opposed to what happens in a shell
    substitution) (bug#40949).
---
 src/fileio.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/fileio.c b/src/fileio.c
index caf077e..1d9a3e1 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -1830,6 +1830,8 @@ the value of that variable.  The variable name should be 
terminated
 with a character not a letter, digit or underscore; otherwise, enclose
 the entire variable name in braces.
 
+If FOO is not defined in the environment, it is not substituted.
+
 If `/~' appears, all of FILENAME through that `/' is discarded.
 If `//' appears, everything up to and including the first of
 those `/' is discarded.  */)