@node Commands
@unnumbered Commands

There are three basic main commands, originally suggested by DJB in his
articles:

@table @command
@item redo
    Forcefully and sequentially build specified targets. This is the
    main command you will explicitly use from the command line. If no
    targets are given, then @file{all} target will be used by default.
@item redo-ifchange
    Rebuild specified targets if they are out-of-date and record them as
    a dependency for the currently run target. This is the main command
    you will use in @file{.do} files.
@item redo-ifcreate
    Record the non-existent file dependency for the currently run
    target. Target will be rebuilt if any of the given files appear. Can
    be used only inside @file{.do} file.
@end table

Pay attention that @command{redo-ifchange} enables parallel builds of
the given targets, but ordinary @command{redo} is not: it builds
specified targets sequentially and stops when error happens.

@option{-x} option can be used to enable tracing (@code{set -x}) of the
currently run shell script @file{.do} file. @option{-xx} option enables
tracing for all invoked @file{.do} files further.

With @option{-j} option you can enable parallel builds, probably with an
infinite number of workers (@code{=0}). Also you can set
@env{$REDO_JOBS} to automatically apply that setting globally.

Read about @ref{Logs, log storage capabilities}.

@option{-log-pid} (@env{$REDO_LOG_PID=1}) can be used to prefix job's
@code{stderr} with the PID, that could be useful during parallel builds.
@option{-d} (@env{$REDO_DEBUG=1}) enables debug messages.

@option{-no-progress} (@env{$REDO_NO_PROGRESS=1}) and
@option{-no-status} (@env{$REDO_NO_STATUS=1}) disable statusline and
progress display. @env{$NO_COLOR=1} disables progress/debug messages
colouring.

By default all build commands use @code{fsync} to assure data is reached
the disk. You can disable its usage with @env{$REDO_NO_SYNC=1}
environment variable, for speeding up the build process.

@command{goredo} determines target is out-of-date by comparing its size,
@code{ctime} and content's hash, if @code{ctime} differs. Depending on
the filesystem you use, probably you can not trust its @code{ctime}
value at all. In that case you can set @env{$REDO_INODE_NO_TRUST=1} to
forcefully verify the hash.

There are other commands that could be found in other implementations too:

@table @command
@item redo-always
    Record current target as an always-do dependency. By definition it
    should be always build. @command{goredo} tries to build it once per
    @strong{run}.
@item redo-stamp
    Record "stamp" dependency. It reads @code{stdin} and stores its hash
    in the dependency database. It is not used anyhow, it is dummy. Read
    about @ref{Stamping, stamping} in the FAQ. It is left only for
    compatibility with some other implementations.
@item redo-targets, redo-ood
    Show all known targets, possibly limited by specified directories.
    @command{redo-ood} shows only the out-of-date ones.
@item redo-sources
    Recursively show all source files the given targets depend on.
@item redo-affects
    It is not in other distributions, but it is some kind of opposite of
    @command{redo-sources} -- shows the targets that will be affected by
    specified files change.
@end table

And there are some maintenance and debug commands:

@table @command
@item redo-cleanup
    Removes either temporary (@option{tmp}), log files (@option{log}),
    or everything related to @command{goredo} (@option{full}).
@item redo-whichdo
    Display @file{.do} search paths for specified target (similar to
    @command{apenwarr/redo}):
@example
$ redo-whichdo x/y/a.b.o
x/y/a.b.o.do
x/y/default.b.o.do
x/y/default.o.do
x/y/default.do
x/default.b.o.do
x/default.o.do
x/default.do
default.b.o.do
default.o.do
default.do
../default.b.o.do
../default.o.do
../default.do
@end example
@item redo-dot
    Dependency
    @url{https://en.wikipedia.org/wiki/DOT_(graph_description_language), DOT}
    graph generator. For example to visualize your dependencies with GraphViz:
@example
$ redo target [...] # to assure that **/.redo/*.rec are filled up
$ redo-dot target [...] > whatever.dot
$ dot -Tpng whatever.dot > whatever.png # possibly add -Gsplines=ortho
@end example

@end table