bash golf problem

threshold.sh

#!/bin/bash
# Input:
#     output this 6
#     do not output this 5
#     output this 7
#
# Output (and a non-zero exit code):
#     output this 6
#     output this 7

THRESHOLD=5

cat test_file |
  ruby -ne "puts \$_ if \$_.split(' ').last.to_i > \"${THRESHOLD}\".to_i" | \
  ruby -e 'out = STDIN.read; puts out; exit(1) if out.length > 0'

Combined above solutions to this:

#!/bin/bash

THRESHOLD=5

! cat test_file | \
  awk "\$NF > $THRESHOLD { print }" | \ # $NF = last field
  egrep ".+"                            # Set exit code if no output,
                                        # negated by preliminary `!`

You can remove the cat and apply the awk line directly to the test_file - if we're still golfing.

awk "\$NF > $THRESHOLD { print }"  test_file

Beautiful! :D

(Whoops! Accidental +1, sorry!)

@telemachus , you dont need print statement, it is the default behaviour

awk -v t=$THRESHOLD '$NF > t' test_file

Untested , but i'm sure it work , and less readable but shorter:

awk '$NF>'$THRESHOLD test_file