Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.

ISALPHA(3)                 Library Functions Manual                 ISALPHA(3)

NAME
     isalpha - alphabetic character test

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     isalpha(int c);

DESCRIPTION
     The isalpha() function tests for any character for which isupper(3) or
     islower(3) is true and for which none of iscntrl(3), isdigit(3),
     ispunct(3), or isspace(3) is true.  In the ``C'' locale, isalpha()
     returns true only for the characters for which isupper(3) or islower(3)
     is true.

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

SEE ALSO
     ctype(3), isalnum(3), isascii(3), isblank(3), iscntrl(3), isdigit(3),
     isgraph(3), islower(3), isprint(3), ispunct(3), isspace(3), isupper(3),
     isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7)

STANDARDS
     The isalpha() function conforms to ANSI X3.159-1989 ("ANSI C89").

CAVEATS
     The argument to isalpha() 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