The following efuns exist for working with strings:
capitalize
clear_bit
crypt
explode
implode
lower_case
next_bit
pluralize
reg_assoc
regexp
replace_string
set_bit
sprintf
sscanf
strcmp
stringp
strlen
strsrch
terminal_colour
test_bit
Beek @ZorkMUD, Lima Bean, IdeaExchange, TMI-2, and elsewhere