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ISALNUM(3)                 Library Functions Manual                 ISALNUM(3)

NAME
     isalnum - alphanumeric character test

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     isalnum(int c);

DESCRIPTION
     The isalnum() function tests for any character for which isalpha(3) or
     isdigit(3) is true.

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

SEE ALSO
     ctype(3), isalpha(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 isalnum() function conforms to ANSI X3.159-1989 ("ANSI C89").

CAVEATS
     The argument to isalnum() 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