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ISALNUM(3)               BSD 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.  For single
     C chars locales (see multibyte(3)), the value of the argument is representable as an unsigned char or
     the value of EOF.  In the ASCII character set, this includes the following characters (preceded by
     their numeric values, in octal):

     060 ``0''     061 ``1''     062 ``2''     063 ``3''     064 ``4''
     065 ``5''     066 ``6''     067 ``7''     070 ``8''     071 ``9''
     101 ``A''     102 ``B''     103 ``C''     104 ``D''     105 ``E''
     106 ``F''     107 ``G''     110 ``H''     111 ``I''     112 ``J''
     113 ``K''     114 ``L''     115 ``M''     116 ``N''     117 ``O''
     120 ``P''     121 ``Q''     122 ``R''     123 ``S''     124 ``T''
     125 ``U''     126 ``V''     127 ``W''     130 ``X''     131 ``Y''
     132 ``Z''     141 ``a''     142 ``b''     143 ``c''     144 ``d''
     145 ``e''     146 ``f''     147 ``g''     150 ``h''     151 ``i''
     152 ``j''     153 ``k''     154 ``l''     155 ``m''     156 ``n''
     157 ``o''     160 ``p''     161 ``q''     162 ``r''     163 ``s''
     164 ``t''     165 ``u''     166 ``v''     167 ``w''     170 ``x''
     171 ``y''     172 ``z''

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

COMPATIBILITY
     The 4.4BSD extension of accepting arguments outside of the range of the unsigned char type in locales
     with large character sets is considered obsolete and may not be supported in future releases.  The
     iswalnum() function should be used instead.

SEE ALSO
     ctype(3), isalnum_l(3), isalpha(3), isdigit(3), iswalnum(3), multibyte(3), ascii(7)

STANDARDS
     The isalnum() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

BSD                             August 21, 2004                            BSD