How to escape shell string in gawk?

[Peng Yu]

Hi,

I can not escape the shell string below. Is there a way to do so? Thanks.

$ tmpdir=$(mktemp -d)
$ echo a > "$tmpdir/a b.txt"
$ awk -v tmpfile="$tmpdir/a b.txt" -e 'BEGIN { "cat " tmpfile |
getline x; print x }'
cat: /tmp/mktemp/tmp.XjMDBFsh9R/a: No such file or directory
cat: b.txt: No such file or directory
$ awk -v tmpfile=$(builtin printf %q "$tmpdir/a b.txt") -e 'BEGIN {
"cat " tmpfile | getline x; print x }'
awk: cmd. line:1: b.txt
awk: cmd. line:1:  ^ syntax error

-- 
Regards,
Peng