#!/bin/bash
t=$(mktemp -d -t) || exit
cd "$t"
cat <<':' >inputfile
grapes are purple
hello fox in the house
bonnet is blue
simple is best
:
echo 'fox' >patternfile
grep -v -F -f patternfile inputfile >newfile
tail newfile /dev/null
IyEvYmluL2Jhc2gKCnQ9JChta3RlbXAgLWQgLXQpIHx8IGV4aXQKY2QgIiR0IgoKY2F0IDw8JzonID5pbnB1dGZpbGUKZ3JhcGVzIGFyZSBwdXJwbGUKaGVsbG8gZm94IGluIHRoZSBob3VzZQpib25uZXQgaXMgYmx1ZQpzaW1wbGUgaXMgYmVzdAo6CgplY2hvICdmb3gnID5wYXR0ZXJuZmlsZQoKZ3JlcCAtdiAtRiAtZiBwYXR0ZXJuZmlsZSBpbnB1dGZpbGUgPm5ld2ZpbGUKCnRhaWwgbmV3ZmlsZSAvZGV2L251bGw=