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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.  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):

     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 isalpha() 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
     iswalpha() function should be used instead.

SEE ALSO
     ctype(3), isalnum_l(3), islower(3), isupper(3), iswalpha(3), multibyte(3), ascii(7)

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

BSD                             August 21, 2004                            BSD