13.4.1 POTFILES.in in po/

The po/ directory should receive a file named POTFILES.in. This file tells which files, among all program sources, have marked strings needing translation. Here is an example of such a file:

# List of source files containing translatable strings.
# Copyright (C) 1995 Free Software Foundation, Inc.

# Common library files
lib/error.c
lib/getopt.c
lib/xmalloc.c

# Package source files
src/gettext.c
src/msgfmt.c
src/xgettext.c

Hash-marked comments and white lines are ignored. All other lines list those source files containing strings marked for translation (see How Marks Appear in Sources), in a notation relative to the top level of your whole distribution, rather than the location of the POTFILES.in file itself.

When a C file is automatically generated by a tool, like flex or bison, that doesn’t introduce translatable strings by itself, it is recommended to list in po/POTFILES.in the real source file (ending in .l in the case of flex, or in .y in the case of bison), not the generated C file.