Question

In bash file, I can write this:

my_program << EOF
Some test
More test
A lot of multi-line text
EOF

This will launch my_program executable and pass three lines of text (or more) to it through a pipe.

Now I want to so same in Makefile (GNU make). I’ve found no standard solution and it’s solved like this:

LaunchMyProgram:
    echo -en "Some test\\nMore test\\nA lot of multi-line text\\n" | my_program

But this look very ugly. Is there more fine solution?

Answer 1

Yes, that is ugly, but there’s not much you can do about it. make executes each line as its own shell script, unless the line ends with a \ continuation character; but then the newline is stripped. This is a little bit cleaner:

all:
    printf 'hi\n\
    there\n\
    how\n\
    are\n\
    you'

Normally I’d use echo here but printf is a bit more portable when it comes to handling escape characters.