islower(3) - Manual pages

NAME

islower — lower-case character test

#include <ctype.h>

int
islower(int c);;

The islower() function tests for any lower-case letters. In the ASCII character set, this includes the following characters:

141 ``a'' 142\``b'' 143\``c'' 144\``d'' 145\``e''

146 ``f'' 147\``g'' 150\``h'' 151\``i'' 152\``j''

153 ``k'' 154\``l'' 155\``m'' 156\``n'' 157\``o''

160 ``p'' 161\``q'' 162\``r'' 163\``s'' 164\``t''

165 ``u'' 166\``v'' 167\``w'' 170\``x'' 171\``y''

172 ``z''

The islower() function returns zero if the character tests false and returns non-zero if the character tests true.

The islower() function conforms to ANSI X3.159-1989 (“ANSI C89”).