isalpha(3) [netbsd man page]

ISALPHA(3)						   BSD 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.

BSD
								  April 17, 2008							       BSD

ISALPHA(3)						     Linux Programmer's Manual							ISALPHA(3)

NAME

       isalnum,  isalpha, isascii, isblank, iscntrl, isdigit, isgraph, islower, isprint, ispunct, isspace, isupper, isxdigit - character classifi-
       cation routines

SYNOPSIS

       #include <ctype.h>

       int isalnum(int c);
       int isalpha(int c);
       int isascii(int c);
       int isblank(int c);
       int iscntrl(int c);
       int isdigit(int c);
       int isgraph(int c);
       int islower(int c);
       int isprint(int c);
       int ispunct(int c);
       int isspace(int c);
       int isupper(int c);
       int isxdigit(int c);

DESCRIPTION

       These functions check whether c, which must have the value of an unsigned char or EOF, falls into a certain character  class  according	to
       the current locale.

       isalnum()
	      checks for an alphanumeric character; it is equivalent to (isalpha(c) || isdigit(c)).

       isalpha()
	      checks  for  an  alphabetic character; in the standard "C" locale, it is equivalent to (isupper(c) || islower(c)).  In some locales,
	      there may be additional characters for which isalpha() is true--letters which are neither upper case nor lower case.

       isascii()
	      checks whether c is a 7-bit unsigned char value that fits into the ASCII character set.  This function is a  BSD	extension  and	is
	      also an SVID extension.

       isblank()
	      checks for a blank character; that is, a space or a tab.	This function is a GNU extension.

       iscntrl()
	      checks for a control character.

       isdigit()
	      checks for a digit (0 through 9).

       isgraph()
	      checks for any printable character except space.

       islower()
	      checks for a lower-case character.

       isprint()
	      checks for any printable character including space.

       ispunct()
	      checks for any printable character which is not a space or an alphanumeric character.

       isspace()
	      checks  for  white-space	characters.   In the "C" and "POSIX" locales, these are: space, form-feed ('f'), newline ('
'), carriage
	      return ('
'), horizontal tab ('	'), and vertical tab ('v').

       isupper()
	      checks for an uppercase letter.

       isxdigit()
	      checks for a hexadecimal digits, i.e. one of 0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F.

RETURN VALUE

       The values returned are nonzero if the character c falls into the tested class, and a zero value if not.

CONFORMING TO

       ANSI - C, BSD 4.3.  isascii() is a BSD extension and is also an SVID extension.	isblank() is a GNU extension.

NOTE

       The details of what characters belong into which class depend on the current locale.  For example, isupper() will  not  recognize  an  A  -
       umlaut as an uppercase letter in the default C locale.

SEE ALSO

       tolower(3), toupper(3), setlocale(3), ascii(7), locale(7)

GNU
								    1995-09-02								ISALPHA(3)