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ISLOWER(P)			    POSIX Programmer's Manual			       ISLOWER(P)

       islower - test for a lowercase letter

       #include <ctype.h>

       int islower(int c);

       The islower() function shall test whether c is a character of class lower in the program's
       current locale; see the	Base  Definitions  volume  of  IEEE Std 1003.1-2001,  Chapter  7,

       The  c  argument is an int, the value of which the application shall ensure is a character
       representable as an unsigned char or equal to the value of the macro EOF. If the  argument
       has any other value, the behavior is undefined.

       The  islower()  function  shall	return non-zero if c is a lowercase letter; otherwise, it
       shall return 0.

       No errors are defined.

       The following sections are informative.

   Testing for a Lowercase Letter
       The following example tests whether the value is a lowercase letter, based on  the  locale
       of the user, then uses it as part of a key value.

	      #include <ctype.h>
	      #include <stdlib.h>
	      #include <locale.h>
	      char *keystr;
	      int elementlen, len;
	      char c;
	      setlocale(LC_ALL, "");
	      len = 0;
	      while (len < elementlen) {
		  c = (char) (rand() % 256);
		  if (islower(c))
		      keystr[len++] = c;

       To  ensure  applications portability, especially across natural languages, only this func-
       tion and those listed in the SEE ALSO section should be used for character classification.



       isalnum() , isalpha() , iscntrl() , isdigit() , isgraph() , isprint() , ispunct()  ,  iss-
       pace()  ,  isupper()  ,	isxdigit()  ,  setlocale()  ,  the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, Chapter 7, Locale, <ctype.h>

       Portions of this text are reprinted and	reproduced  in	electronic  form  from	IEEE  Std
       1003.1,	2003  Edition,	Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003  by
       the  Institute  of  Electrical  and  Electronics Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003				       ISLOWER(P)
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