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ISLOWER(3) Library Functions Manual ISLOWER(3) NAME islower - lower-case character test LIBRARY Standard C Library (libc, -lc) SYNOPSIS #include <ctype.h> int islower(int c); DESCRIPTION The islower() function tests for any lower-case letter for which none of iscntrl(3), isdigit(3), ispunct(3), or isspace(3) is true. In the ``C'' locale, islower() returns true only for the characters defined as lower- case letters. RETURN VALUES The islower() function returns zero if the character tests false and returns non-zero if the character tests true. SEE ALSO ctype(3), isalnum(3), isalpha(3), isascii(3), isblank(3), iscntrl(3), isdigit(3), isgraph(3), isprint(3), ispunct(3), isspace(3), isupper(3), isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7) STANDARDS The islower() function conforms to ANSI X3.159-1989 ("ANSI C89"). CAVEATS The argument to islower() must be EOF or representable as an unsigned char; otherwise, the behavior is undefined. See the CAVEATS section of ctype(3) for more details. NetBSD 10.99 April 17, 2008 NetBSD 10.99