sed in makefile, usage
I am in the process of learning makefile creation.
Current target is to scan the $(SOURCEDIR)
for .c
files and create (according to that lise of .c
file paths in the format of /path/file.c
) a nice $(VPATH)
so I do not need to use recursive makefiles (aka pain in the a..).
Atm I am stuck with this, where $(SOURCETREE)
will be empty on $(ECHO)
SOURCES := $(shell find $(SOURCEDIR) -name '*.c')
SOURCETREE := $(dir $(SOURCES))
SOURCETREE := $(shell $(ECHO) $(SOURCETREE) | $(SED) -e "s/[[:space:]]/\n/g" | uniq | $(SED) -e "s/\n/[[:space:]]/g");
Maybe I just do not get the point (got late again :/ )
Thanks for any help.
Note: In a bash shell it开发者_如何学运维 works perfectly on my linux workbox (I replace thevariables accordingly) Note: I am no sed pro, so please explain if you do an voodoo with sed, thank you
Comments:
Remove the backticks. They are unnecessary; the
$(shell)
function already captures the command's output.The echo/sed/uniq/sed chain can be replaced by ls/uniq.
ls
will print one file name per line so no need for the replace-and-undo song and dance.It looks like you're losing the result from
$(dir)
because you use$(SOURCES)
rather than$(SOURCETREE)
in the third assignment.
Result:
SOURCES := $(shell find $(SOURCEDIR) -name '*.c')
SOURCETREE := $(dir $(SOURCES))
SOURCETREE := $(shell ls $(SOURCETREE) | uniq);
Actually, even this shortened shell invocation is unnecessary. The $(sort)
function will sort a list of names and remove duplicates. From make's documentation: "Incidentally, since sort removes duplicate words, you can use it for this purpose even if you don't care about the sort order."
SOURCES := $(shell find $(SOURCEDIR) -name '*.c')
SOURCETREE := $(sort $(dir $(SOURCES)))
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