REDO-WHICHDO(1)             General Commands Manual            REDO-WHICHDO(1)

NAME
       redo-whichdo - print search paths for dofiles to build a redo target

SYNOPSIS
       redo-whichdo target

DESCRIPTION
       redo(1) is a tool for building files and for rebuilding them if any of
       their dependencies have changed.  redo-whichdo prints all dofiles that
       redo(1) will look for to build the target.  If the exit code of
       redo-whichdo indicates success, the last filename is the filename of
       the dofile that redo(1) will actually use to build the target.

       redo-whichdo prints the filename for a dofile that redo(1) could use to
       build the target.  If the dofile exists, redo-whichdo exits with a
       status code indicating success.  If the dofile does not exist,
       redo-whichdo either repeats the previous action with a fallback
       filename or exits with a status code indicating error if redo-whichdo
       can not find a dofile to build the target.

       If standard output is a terminal, redo-whichdo separates filenames by
       newline characters. Otherwise, redo-whichdo separates filenames by null
       characters.  Shell scripts that act on the output of redo-whichdo can
       pipe it to xargs(1) invoked with the -0 option to handle the filenames.

EXAMPLES
       Consider a root directory containing only the three dofiles a.do,
       default.b.do, default.c.do, and a folder d.  For the targets, a, a.b,
       and a.b.c, d/a.b.c, the output of redo-whichdo(1) would be these:

       a
              /a.do

       a.b
              /a.b.do
              /default.b.do

       a.b.c
              /a.b.c.do
              /default.b.c.do
              /default.c.do

       d/a.b.c
              /d/a.b.c.do
              /d/default.b.c.do
              /d/default.c.do
              /d/default.do
              /default.b.c.do
              /default.c.do

NOTES
       A dofile used to build a target is a dependency of that target: If
       redo(1) determines that the dofile used to build a target has changed,
       the target will be rebuilt.

       All non-existent dofiles searched for while building a target are non-
       existence dependencies of that target: If redo(1) finds that a
       previously searched for non-existent dofile exists, the target will be
       rebuilt.

HISTORY
       redo-whichdo was designed by Avery Pennarun and Nils Dagsson Moskopp as
       part of Avery Pennarun's redo implementation and independently
       implemented by Nils Dagsson Moskopp.

AUTHOR
       redo-whichdo and this man page were written by Nils Dagsson Moskopp.

COPYRIGHT
       Copyright (C) 2018-2019 Nils Dagsson Moskopp.  License AGPLv3+: GNU
       Affero GPL version 3 or later
       <http://www.gnu.org/licenses/agpl-3.0.html>.  This is free software:
       you are free to change and redistribute it. There is NO WARRANTY, to
       the extent permitted by law.

SEE ALSO
       redo(1), redo-ifchange(1), redo-ifcreate(1), redo-targets(1)

                                                               REDO-WHICHDO(1)