.. COMMENT: This file was automatically generated from the file:
.. COMMENT:    @NEWLIB_FILENAME@
.. COMMENT: Generateed on: @DATE@

.. isalnum:

isalnum - Alphanumeric character predicate (GOAL)
----------------------------------------------------------------
.. index:: isalnum
.. index:: alphanumeric character predicate
.. index:: isalnum_l



**CALLING SEQUENCE:**

.. code-block:: c

	#include <ctype.h>
	int isalnum(int c);

	#include <ctype.h>
	int isalnum_l(int c, locale_t locale);




**STATUS CODES:**

*isalnum*,*isalnum_l* return non-zero if ``c`` is a letter or a digit.



**DESCRIPTION:**

*isalnum* is a macro which classifies singlebyte charset values by table
lookup.  It is a predicate returning non-zero for alphabetic or
numeric ASCII characters, and *0* for other arguments.  It is defined
only if ``c`` is representable as an unsigned char or if ``c`` is EOF.

*isalnum_l* is like *isalnum* but performs the check based on the
locale specified by the locale object locale.  If ``locale`` is
LC_GLOBAL_LOCALE or not a valid locale object, the behaviour is undefined.

You can use a compiled subroutine instead of the macro definition by
undefining the macro using ``#undef isalnum`` or ``#undef isalnum_l``.


**ORIGIN**

The information in this section was generated from documentation
included with the `Newlib C Library <https://sourceware.org/newlib/>`_.