&: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
------------------
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 $(addprefix...)
(This assumes you have appropriate make variables src, PWD and
abs_src.)
The assumption is that filenames are usually lowercase and
variables usually uppercase. Otherwise, use another syntax:
+&/ => sub/dir/ or nothing
&_ => sub_dir_ or TOP_
-&=_ => sub_dir or TOP
+&. => sub/dir or .
+ (This implies that `&./' works roughly like `&/', although
+ it can produce a needless `./')
-&/ => sub/dir/ or nothing
-&=/ => sub/dir or .
+&= => sub_dir or TOP
+^^^ rarely needed. TBD, maybe one of
+ &._ &_. &\_ &% &$_
+ &<varnameprefix> &[varnameprefix]
+ $(patsubst %_,&_,%)
-&,lc => $(top_srcdir)/sub/dir/lc
-&,/ => $(top_srcdir)/sub/dir/
+&^lc => $(top_srcdir)/sub/dir/lc
+&^/ => $(top_srcdir)/sub/dir/
+&^. => $(top_srcdir)/sub/dir
-&;lc => $(top_srcdir)/lc
-&;/ => $(top_srcdir)/
+&~lc => $(top_srcdir)/lc
+&~/ => $(top_srcdir)/
+&~. => $(top_srcdir)
In general:
- = return subdir without delimiter (not allowed with `,' `;')
- , pathname of this subdirectory in source tree
- ; pathname of top level of source tree
- / terminates the escape (needed if next is not lwsp or space)
+ ^ pathname of this subdirectory in source tree
+ ~ pathname of top level of source tree
+ / terminates the path escape } needed if next is
+ _ terminates the var escape } not lwsp or space)
+ . terminates path escape giving dir name (excluding /)
+ = terminates var escape giving only prefix part (rarely needed)
lwsp starts multi-word processing (see below)
So pathname syntax is a subset of:
- '&' [ ',' | ';' ] [ lc | '/' ]
+ '&' [ '^' | '~' ] [ lc | '/' | '.' | '=' ]
&& => && for convenience in shell runes
-\& => & general escaping mechanism
+&@ => & general escaping mechanism
+&&@ => && @ after any number of & vanishes
+
+&$VARIABLE $(sub/dir/VARIABLE)
+ VARIABLE is ASCII starting with a letter and matching \w+
& 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.
&:-include filename tolerate nonexistent file
filenames are relative to $(top_srcdir)
+&:section number [ident]
+ Sections will be read by make in order, first by number
+ and only then by input file (in order passed
+ to generate ie that specified in configure.ac).
+ Number is \d+; order is lexical.
+ Default section number is `5'.
+ Section numbers may not contain only `0'.
+ Section is local to &:include'd files (reset to `5'
+ on entry, restored on return).
+ Ident is [A-Za-z][A-Z0-9a-z/_-]+ and is currently unused,
+ other than appearing in output. When used, will default
+ to source-relative input file name excluding .sd.mk.
+
&!<lwsp> disables & until EOL (and then disappears)
&# delete everything to end of line
(useful if the RHS contains unrecognised & constructions)
-&!STUFF
+&:changequote STUFF
changes the escape sequence from & to literally STUFF
STUFF may be any series of of non-whitespace characters,
- and is terminated by EOL or lwsp. &!STUFF and the lwsp
- are discarded.
+ and is terminated by EOL or lwsp. The whole line is
+ discarded.
After this, write STUFF instead of &, everywhere.
The effect is global and lasts until the next setting.
it back before using &:include.
Notably
- STUFFSTUFF => STUFFSTUFF
- \STUFF => STUFF
- STUFF!& set escape back to &
+ STUFFSTUFF => STUFFSTUFF
+ STUFF@ => STUFF
+ STUFF:changequote & => set escape back to &
&TARGETS_things
- Handled specially. If mentioned, declares that this
+ Handled specially. If mentioned at the start of a line
+ (possibly following whitespace), declares that this
subdir ought to have a target `things'. The rule will be
&/things:: $(&TARGETS_things)
which recursively implies this directory's `things'.
Must be spelled exactly &TARGETS_things. &_TARGETS_things,
- for example, is not magic. But mentioning &TARGETS_things in
- a #-comment *does* work because the & filter does not care
- about comments.
+ for example, is not magic. To make the target exist
+ without providing any prerequisites for it, write a line
+ containing just `&TARGETS_things +='.
`all' is extra special: every directory has an `all'
target, which corresponds to &TARGETS.
+DRAFT - MACRO ASSISTANCE FACILITY
+---------------------------------
+
+Thanks to Mark Wooding.
+
+ &:macro NAME
+ STUFF
+ &:endm
+
+expands to
+
+ define %NAME
+ STUFF (with `$'s doubled except before a digit)
+ endef
+ NAME = $(eval $(call %NAME,$1,$2,$3,$4,$5,$6,$7,$8,$9))
+
+and
+
+ &(NAME ARG,ARG,...)
+
+expands to
+
+ $(call NAME,ARG,ARG,...)
+
+with `$'s doubled.
+
Subdirectory and variable naming
--------------------------------