$ echo "test exit codes"
test exit codes

$ false
[1]

$ sh -c "exit 42"
[42]

$ sh -c "echo oops && exit 1"
oops
[*]

$ export MY_VAR=hello
$ echo $MY_VAR
hello

$ cd /tmp
$ pwd
/tmp

$ echo "line 1" && echo "" && echo "line 3"
line 1

line 3

$ echo "match ..."
match ...