ISALPHA(3)

NAME
3.2 `isalpha'--alphabetic character predicate

SYNOPSIS
     #include <ctype.h>
     int isalpha(int C);

DESCRIPTION
`isalpha' is a macro which classifies ASCII integer values by table lookup. It is a predicate returning non-zero when C represents an alphabetic ASCII character, and 0 otherwise. It is defined only when `isascii'(C) is true or C is EOF.
   You can use a compiled subroutine instead of the macro definition by undefining the macro using ``#undef isalpha''.

RETURNS
`isalpha' returns non-zero if C is a letter (`A'-`Z' or `a'-`z').

PORTABILITY
`isalpha' is ANSI C.
   No supporting OS subroutines are required.

SEE ALSO
isalpha is part of the library. The full documentation for is maintained as a Texinfo manual. If info and are properly installed at your site, the command

    info

will give you access to the complete manual.