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ISLOWER(3)               BSD Library Functions Manual               ISLOWER(3)

     islower -- lower-case character test

     Standard C Library (libc, -lc)

     #include <ctype.h>

     islower(int c);

     The islower() function tests for any lower-case letters.  The value of the argument must be repre-sentable representable
     sentable as an unsigned char or the value of EOF.

     In the ASCII character set, this includes the following characters (with their numeric values shown in

     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''

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

     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
     iswlower() function should be used instead.

     ctype(3), isalnum_l(3), iswlower(3), tolower(3), ascii(7)

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

BSD                              July 17, 2005                             BSD

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