Libft(16) - isalpha

Libft(16) - isalpha

 

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.
     The value of the argument must be 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), ascii(7)

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

BSD                              July 17, 2005                             BSD

• 알파벳이면 non-zero 리턴 (대문자 1 리턴, 소문자 2 리턴)
• 알파벳이 아니면 0 리턴

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