about summary refs log tree commit diff
diff options
context:
space:
mode:
authorChristian Neukirchen <chneukirchen@gmail.com>2015-09-06 19:40:27 +0200
committerChristian Neukirchen <chneukirchen@gmail.com>2015-09-06 19:40:27 +0200
commit6acb10fc71441e95909398a59906b18e04cf314d (patch)
tree19416d65768a9b264e48a7821f66038cbb78f055
parentd995dedd294a8f91adf67a48107fb2cca3bc5515 (diff)
downloadredo-c-6acb10fc71441e95909398a59906b18e04cf314d.tar.gz
redo-c-6acb10fc71441e95909398a59906b18e04cf314d.tar.xz
redo-c-6acb10fc71441e95909398a59906b18e04cf314d.zip
Add NOTES
-rw-r--r--NOTES32
1 files changed, 32 insertions, 0 deletions
diff --git a/NOTES b/NOTES
new file mode 100644
index 0000000..0df7a6b
--- /dev/null
+++ b/NOTES
@@ -0,0 +1,32 @@
+= Notes about the redo-c implementation of redo
+
+* Without arguments, `redo` behaves like `redo all`.
+
+* `.do` files always are executed in their directory, arguments are
+  relative paths.
+
+* Standard output of `.do` files is only captured as build product if
+  `redo -s` is used, or the environment variable `REDO_STDOUT` is set to 1.
+  Else, standard output is simply displayed.
+
+* Non-executable `.do` files are run with `/bin/sh -e`.
+  `redo -x` can be utilized to use `/bin/sh -e -x` instead, for
+  debugging `.do` files or verbose builds.
+
+* Executable `.do` files are simply executed, and should have a shebang line.
+
+* When a target makes no output, no target file is created.  The target
+  is considered always out of date.
+
+* `default.do` files are checked in all parent directories up to `/`.
+
+* Parallel builds can be started with `redo -j N`, this uses a job
+  broker similar to but not compatible with GNU make.
+
+* To detect whether a file has changed, we first compare `ctime` and
+  in case it differs, a SHA2 hash of the contents.
+
+* Dependencies are tracked in `.dep.BASENAME` files all over the tree.
+  This is an implementation detail.
+
+* Builds can be started from every directory and should yield same results.