Karls-Mac-mini:monks karl$ export foo=b
Karls-Mac-mini:monks karl$ echo ${foo} | perl -ne '( /.{2,}/ ) ? exit 1 : exit 0;'
Karls-Mac-mini:monks karl$ echo $?

Karls-Mac-mini:monks karl$ export foo=bar
Karls-Mac-mini:monks karl$ echo ${foo} | perl -ne '( /.{2,}/ ) ? exit 1 : exit 0;'
Karls-Mac-mini:monks karl$ echo $?