islower() - lower-case character test
#include <ctype.h>
int islower (int c)
The islower(3) function tests for any lower-case letters. In the POSIX/C locale, this includes the following characters:
| "a" | "b" | "c" | "d" | "e" |
| "f" | "g" | "h" | "i" | "j" |
| "k" | "l" | "m" | "n" | "o" |
| "p" | "q" | "r" | "s" | "t" |
| "u" | "v" | "w" | "x" | "y" |
| "z" |
The islower(3) function returns zero if the character tests false and returns non-zero if the character tests true.
isalnum(3)
isalpha(3)
isblank(3)
iscntrl(3)
isdigit(3)
isgraph(3)
isprint(3)
ispunct(3)
isspace(3)
isupper(3)
isxdigit(3)
tolower(3)
toupper(3)