CODEWITHSUNDEEP
bashshellmakefile
Tesla
Tesla

Reputation: 822

Simple echo in makefile escape issue

this is a really simple issue, but I am struggling to figure out how to do it. I have a makefile, and in the make file I have the following line:

echo "java packet.Program $1 $2 $3 $4" > programScript

My question is this: How do I make this line print exactly what is in the quotes? Right now, it keeps trying to interpret $1, $2, $3, $4 as parameters. I want the makefile, when run, to echo exactly "java packet.Program $1 $2 $3 $4" char for char. The '$' are giving me an issue.

Thanks.

Edit:

To clarify the issue. When I type "echo 'java packet.Program $1 $2 $3 $4' > programScript" into the terminal, it prints it exactly how it should. But when I put the same line into my makefile file, and run "make", it doesnt print anything after "java packet.Program".

Upvotes: 1

Views: 3020

Answers (3)

built1n
built1n

Reputation: 1546

Use $$ to echo a $ in a Makefile. Reference: Escaping in makefile

Upvotes: 0

rici
rici

Reputation: 241971

make does not attempt to parse command lines, so "$name" and '$name' are treated the same by make; in both cases, the $name will be substituted with the value of the make variable $(name). In neither case will the shell see the $.

If you want to insert a literal $ in a command in a makefile, you need to write $$.

So, for example:

show_a_dollar:
        echo '$$a'

show_a_variable:
        echo "$$a"

In the first make rule, the resulting action is:

echo '$a'

which will echo, literally, $a. In the second, the resulting action is

echo "$a"

which will echo the value of the environment variable a.

So you need to consider both make expansion rules, which require you to double the $ to $$, and shell expansion rules, which require the command-line argument to be within single-quotes:

echo 'java packet.Program $$1 $$2 $$3 $$4' > programScript

Upvotes: 3

yarivt
yarivt

Reputation: 106

Use either single quote

echo 'java packet.Program $1 $2 $3 $4' > programScript

Or, escape them:

echo "java packet.Program \$1 \$2 \$3 \$4" > programScript

Upvotes: 0

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