Why basename in Makefile does not work as expected? - makefile

TESTS=test/hello.c
try:
#for t in $(TESTS); do echo $(basename $$t); done
Running "make" I get
~ make
test/hello.c
This is strange because I expected to get the base name "hello.c". Any explanation? Thanks.

The trouble is that you're trying to use the Make directive basename inside the shell for loop. Make will expand the $(basename ...) statement first (so $(basename $$t) becomes $t), then pass the command
for t in test/hello.c; do echo $t; done
to the shell.
This will give test/hello:
#for t in $(basename $(TESTS)); do echo $$t; done
and this will give hello.c:
#for t in $(notdir $(TESTS)); do echo $$t; done

Related

Rules of executing shell command in Makefile

When I executed command make, I got an error message
Makefile:4: *** missing separator. Stop.
The command in Makefile is:
$(shell ./makejce common/jce jce)
What's wrong with it?
-------makejce---------
#!/bin/bash
FLAGS=""
local_protoc=""
dir0=`pwd`
dir=`pwd`
......
if [ $# -gt 1 ]
then
mkdir -p $2
cd $2
dir=`pwd`
cd $dir0
fi
cd $1
jce_dir=`pwd`
#sub dir
for d in `ls -d */`
do
if [ -d $d ]
then
cd $d
for f in `find . -name '*.jce'`
do
${local_protoc} ${FLAGS} --dir=${dir} $f
done
cd $jce_dir
fi
done
#current dir
for f in `ls *.jce`
do
${local_protoc} ${FLAGS} --dir=${dir} $f
done
cd $dir0
-----makefile------
......
$(shell ./makejce common/jce jce)
......
With so little info it looks extremely bizarre (why are you running all the build steps in a shell script then invoking that script with a shell makefile function? The entire point of a makefile is to manage the build steps...) but without more information I'll just answer your specific question:
The make shell function works like backticks or $(...) in shell scripts: that is it runs the command in a shell and expands to the stdout of the command.
In your makefile if you have:
$(shell echo hi)
then it runs the shell command echo hi and expands to the stdout (i.e., hi). Then make will attempt to interpret that as some makefile text, because that's where you have put the function invocation (on a line all by itself). That's a syntax error because make doesn't know what to do with the string hi.
If you want to run a shell function then either (a) redirect its output so it doesn't output anything:
$(shell ...command... >/dev/null 2>&1)
or (b) capture the output somewhere that it won't bother make, such as in a variable like this:
_dummy := $(shell ...command...)
(by using := here we ensure the shell function is evaluated when the makefile is parsed).

How to use shell script in makefile

all:
#for dir in $(DIRS); do make -C $$dir; done
I can't understand symbol #. Why use # ?
It just avoids echoing the command... Google is your friend

Delayed Windows cmd echo with GNU Make environment

I have few simple targets which create some files for me.
Example:
$(MAKE_INA):
#echo Building ASM compilation flags file $(notdir $(MAKE_INA))
#$(foreach i, $(sort $(ASMFLAGS) $(PFLAGS) $(ALL_INC_DIR) $(cppGetPreProcessorDefines)), $(shell echo $i >> $# ))
The target works fine, the file is being created and echo text displayed, but in that order (first the file is build then the echo is shown on cmd.exe console).
I guess that is related somehow with output buffering, but I was not able to find the way to flush the echos immediately.
Any hint? Is it even possible?
I am using Gnu Make 4.0
You are mixing up contexts here.
The first #echo line is a recipe line and is run by the shell when the target runs.
The second $(foreach) line is within the rule but is a make context line and is evaluated by make before running the recipe lines. Within that line $(shell) is also a make command and is run during the make expansion of the recipe instead of being run by the shell at recipe execution time.
To do what you want you can just use:
$(MAKE_INA):
#echo Building ASM compilation flags file $(notdir $(MAKE_INA))
#printf "%s\\n" $(sort $(ASMFLAGS) $(PFLAGS) $(ALL_INC_DIR) $(cppGetPreProcessorDefines)) >> $#
Which does the echoing at recipe execution time (so has the right order) and uses a single call to the printf built-in to output to the file instead of running N calls to echo.
Edit: For Windows cmd.exe compat you need to use echo $i >> $# & as the $(foreach) body so that cmd.exe runs multiple commands correctly.
If you did want to keep the N echo calls then you could use:
$(MAKE_INA):
#echo Building ASM compilation flags file $(notdir $(MAKE_INA))
#$(foreach i, $(sort $(ASMFLAGS) $(PFLAGS) $(ALL_INC_DIR) $(cppGetPreProcessorDefines)), echo $i >> $#; ))
Which has the $(foreach) output echo XXX >> $#; ....; echo ZZZ >> $#; as the recipe line to then execute during recipe execution.

If statement in makefile

I found that I can use ifneq in makefile and I tried to compare 0 and the output of command stat:
#for f in `find $(PATH_PAGES) -name *.hbs`; do \
ifneq "`stat -c '%Y' $$f`" "0";
//some code here
endif
done
But in terminal I've got an error: ifneq: command not found
Is there a different way to compare this or maybe I'm doing something wrong?
In this case you don't want to use Make's ifneq, because it does text substitution before handing over the command to the shell, but you have a shell loop that needs to do different things in each iteration depending on the output of a shell command.
Use the shell if instead:
if [ "`stat -c '%Y' $$f`" != "0" ]; then
//some code here
fi
If you want to use makefile's if condition then there should not be [TAB] before the if statement because if you specify [TAB] then it is treated as shell command thats why you are getting error that ifneq:command not found its not there in shell.
May be this Conditionals in Makefile: missing separator error?
can help in getting better understanding with makefiles
I found that I needed to prepend the if with a #, and backslashes proved to be necessary as well -
#if [ "`stat -c '%Y' $$f`" != "0" ]; then\
echo hello world;\
fi

Shell scripting debug help - Iterating through files in a directory

#!/bin/sh
files = 'ls /myDir/myDir2/myDir3/'
for file in $files do
echo $file
java myProg $file /another/directory/
done
What i'm trying to do is iterate through every file name under /myDir/myDir2/myDir3/, then use that file name as the first argument in calling a java program (second argument is "/another/directory")
When I run this script: . myScript.sh
I get this error:
-bash: files: command not found
What did I do wrong in my script? Thanks!
Per Neeaj's answer, strip off the whitespace from files =.
Better yet, use:
#!/bin/sh -f
dir=/myDir/MyDir2/MyDir3
for path in $dir/*; do
file=$(basename $path)
echo "$file"
java myProg "$file" arg2 arg3
done
Bash is perfectly capable of expanding the * wildcard itself, without spawning a copy of ls to do the job for it!
EDIT: changed to call basename rather than echo to meet OP's (previously unstated) requirement that the path echoed be relative and not absolute. If the cwd doesn't matter, then even better I'd go for:
#!/bin/sh -f
cd /myDir/MyDir2/MyDir3
for file in *; do
echo "$file"
java myProg "$file" arg2 arg3
done
and avoid the calls to basename altogether.
strip off the whitespace in and after files = as files=RHS of assignment
Remove the space surrounding the '=' : change
files = 'ls /myDir/myDir2/myDir3/'
into:
files='ls /myDir/myDir2/myDir3/'
and move the 'do' statement to its own line:
for file in $files
do
....
quote your variables and no need to use ls.
#!/bin/sh
for file in /myDir/myDir2/*
do
java myProg "$file" /another/directory/
done

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