3

Can I get arguments that happen to be AWK options passed directly to a pure AWK script?

Example script:

#!/usr/bin/env -S awk -f
BEGIN { if (ARGV[1] == "-h") print "whoop" }

I want ./myscript -h to print whoop. But AWK gets the -h first and prints its usage instead.

Running ./myscript -- -h works but I can't get -- working in the shebang because of the -f.

I know I could use a shell script with AWK in instead.

  • I'm not on a Unix that allows the multi argument style #! line that you use, so I can't test this: Add -- at the end of the #! line. – Kusalananda Mar 12 at 23:50
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    @Kusalananda, that would result in env -S awk -f -- ./myscript -h, while what I think they need is env -S awk -f ./myscript -- -h. I think that's what the second to last paragraph is trying to say. – ilkkachu Mar 12 at 23:55
  • I think that can't be done with just the #! line, a shell script sounds like a good idea. – ilkkachu Mar 12 at 23:57
  • @ilkkachu Yeah, that sounds about right. – Kusalananda Mar 12 at 23:57
  • @Kusalananda No Unix allows multi argument style #!. IIRC FreeBSD used to, but that was long time ago. – Uncle Billy Mar 13 at 6:49
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For the sake of the challenge, it could be done with the FreeBSD env or with GNU env >= 8.30 (already assumed by the OP) in a shebang:

#! /usr/bin/env -S sh -c 'exec awk -f "$0" -- "$@"'
BEGIN { for(i = 1; i < ARGC; i++) print ARGV[i] }
./myscript -h 1 2 3
-h
1
2
3

It doesn't mean that it's a good idea, though.

You could try this, instead:

#! /bin/sh
BEGIN { 2>"/dev/null"
        exec awk -f "$0" "--" "$@"
}
BEGIN { for(i = 1; i < ARGC; i++) print ARGV[i] }

This assumes that you don't have a BEGIN command in your PATH.

| improve this answer | |
2

If you have GNU awk you can use this

#!/usr/bin/gawk --exec
BEGIN { print "==>",ARGV[1],"<==" }

Sample use

./a -h
 ==> -h <==

I haven't tested it, but the mawk variant appears to use -W exec instead of --exec. GNU gawk claims to support this too, but it doesn't work with #!.

| improve this answer | |
  • It may work using the same env -S trick the user is already using. – Kusalananda Mar 13 at 7:05

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