CODEWITHSUNDEEP
stringbashfilevariablesawk
Michael Gruenstaeudl
Michael Gruenstaeudl

Reputation: 1783

Passing two variables instead of two files to awk

Assume two multi-line text files that are dynamically generated during execution of a bash shell script: file1 and file2

$ echo -e "foo-bar\nbar-baz\nbaz-qux" > file1
$ cat file1
foo-bar
bar-baz
baz-qux

$ echo -e "foo\nbar\nbaz" > file2
$ cat file2
foo
bar
baz

Further assume that I wish to use awk involving an operation on the text strings of both files. For example:

$ awk 'NR==FNR{var1=$1;next} {print $var1"-"$1}' FS='-' file1 FS=' ' file2

Is there any way that I can skip having to save the text strings as files in my script and, instead, pass along the text strings to awk as variables (or as here-strings or the like)?

Something along the lines of:

$ var1=$(echo -e "foo-bar\nbar-baz\nbaz-qux")
$ var2=$(echo -e "foo\nbar\nbaz")
$ awk 'NR==FNR{var1=$1;next} {print $var1"-"$1}' FS='-' "$var1" FS=' ' "$var2"
# awk: fatal: cannot open file `foo-bar
# bar-baz
# baz-qux' for reading (No such file or directory)

Upvotes: 0

Views: 276

Answers (1)

Ed Morton
Ed Morton

Reputation: 203502

$ awk '{print FILENAME, FNR, $0}' <(echo 'foo') <(echo 'bar')
/dev/fd/63 1 foo
/dev/fd/62 1 bar

Upvotes: 1

Related Questions