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

NAME
       redo-stamp - rebuild target files depending on data given on standard
       input

SYNOPSIS
       [command] | redo-stamp

DESCRIPTION
       redo(1) is a tool for building files and for rebuilding them if any of
       their dependencies have changed.  redo-stamp, when invoked from a
       dofile, adds a dependency of the current redo(1) target on the data
       given on standard input. If the data given on standard input to
       redo-stamp has not changed since the last build, the current redo(1)
       target is not rebuilt and marked as up to date. To ensure that
       redo-stamp checks the current target's validity, one can use
       redo-always(1) to mark the current target as always out of date.

EXAMPLES
       Consider the following two files all.do and b.do:

       all.do
              #!/bin/sh
              redo-ifchange b

       b.do
              #!/bin/sh
              redo-always
              echo 'input a line of text:' >&2
              line | redo-stamp
              date +%s

       Invoking redo(1) in a directory with these files will build a file
       named b containing a timestamp. The next time redo(1) is invoked, it
       will only rebuild b if the output of line(1) changed since the last
       build. This can be verified by invoking redo(1) repeatedly and
       examining the timestamp b after each invocation, then changing the
       input to line(1), invoking redo(1) again and examining the timestamp
       again.

HISTORY
       redo-stamp was designed by Avery Pennarun and implemented by Nils
       Dagsson Moskopp.

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

COPYRIGHT
       Copyright (C) 2014-2017 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 create and redistribute it. There is NO WARRANTY, to
       the extent permitted by law.

SEE ALSO
       redo(1), redo-always(1), redo-dot(1), redo-ifchange(1),
       redo-ifcreate(1), redo-ood(1), redo-sources(1), redo-targets(1)

BUGS
       None so far.

                                                                 REDO-STAMP(1)