X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?p=subdirmk.git;a=blobdiff_plain;f=README;h=518dd087d853308b13e07aab805349714288d26e;hp=c9e4c0f9234f2fe42bac8187dd98c88784bb417a;hb=d817b49007e60b0e7392f23caf08dc0328eb32de;hpb=0a6ac67828982aca4e3c8ac73669420a30c70f34;ds=sidebyside diff --git a/README b/README index c9e4c0f..518dd08 100644 --- a/README +++ b/README @@ -105,6 +105,19 @@ is already provided in subdirmk, for you to reference like this: &:include subdirmk/clean.sd.mk For example you could put that in Perdir.sd.mk. +The top-level Subdir.sd.mk is the first makefile included after the +autogenerated `main.mk' which merely has some basic settings and +includes. So if you want to get in early and set global variables, +put them near the top of Subdir.sd.mk. + +subdirmk's filter script itself sets (only) these variables: + top_srcdir + abs_top_srcdir + SUBDIRMK_MAKEFILES + MAKEFILE_TEMPLATES +You are likely to want to define $(PWD), and shorter names for +top_srdir and abs_top_srcdir (we suggest $(src) and $(abs_src)). + Global definitions ------------------ @@ -161,22 +174,22 @@ Path construction &-expansions are built from the following: Relative paths in... build source - This directory & &, - Top level . &; + This directory & &^ + Top level . &~ In more detail, with all the various options laid out: Recommended Relative paths in... Absolute paths in... for build source build source - This lc &file &,file $(PWD)/&file $(abs_src)/&file - directory any &/file &,/file $(PWD)&/file $(abs_src)/&/file - several & f g h &, f g h $(addprefix...) + This lc &file &^file $(PWD)/&file $(abs_src)/&file + directory any &/file &^/file $(PWD)&/file $(abs_src)/&/file + several & f g h &^ f g h $(addprefix...) - Top lc file &;file - level any file &;/file $(PWD)/file $(abs_src)/file + Top lc file &~file + level any file &~/file $(PWD)/file $(abs_src)/file .mk.in file $(src)/file $(PWD)/file $(abs_src)/file - several f g h &; f g h $(addprefix...) + several f g h &~ f g h $(addprefix...) (This assumes you have appropriate make variables src, PWD and abs_src.) @@ -211,28 +224,28 @@ empty string). &/ => sub/dir/ or nothing &=/ => sub/dir or . -&,lc => $(top_srcdir)/sub/dir/lc -&,/ => $(top_srcdir)/sub/dir/ +&^lc => $(top_srcdir)/sub/dir/lc +&^/ => $(top_srcdir)/sub/dir/ -&;lc => $(top_srcdir)/lc -&;/ => $(top_srcdir)/ +&~lc => $(top_srcdir)/lc +&~/ => $(top_srcdir)/ In general: - = return subdir without delimiter (not allowed with `,' `;') - , pathname of this subdirectory in source tree - ; pathname of top level of source tree + = return subdir without delimiter (not allowed with `^' `~') + ^ pathname of this subdirectory in source tree + ~ pathname of top level of source tree / terminates the escape (needed if next is not lwsp or space) lwsp starts multi-word processing (see below) So pathname syntax is a subset of: - '&' [ ',' | ';' ] [ lc | '/' ] + '&' [ '^' | '~' ] [ lc | '/' ] && => && for convenience in shell runes \& => & general escaping mechanism & thing thing... & -&, thing thing... & -&; thing thing... & +&^ thing thing... & +&~ thing thing... & Convenience syntax for prefixing multiple filenames. Introduced by & followed by lwsp where lc could go. Each lwsp-separated non-ws word is prefixed by &/ etc.