1 files changed, 3 insertions, 0 deletions

diff --git a/src/callproc.c b/src/callproc.c
index 2596f9019e4..3c77238cfb6 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -219,7 +219,10 @@ static mode_t const default_output_mode = 0666;
 DEFUN ("call-process", Fcall_process, Scall_process, 1, MANY, 0,
        doc: /* Call PROGRAM synchronously in separate process.
 The remaining arguments are optional.
+
 The program's input comes from file INFILE (nil means `/dev/null').
+If you want to make the input come from an Emacs buffer, use
+`call-process-region' instead.
 
 Third argument DESTINATION specifies how to handle program's output.
 If DESTINATION is a buffer, or t that stands for the current buffer,