1TOLOWER(3P)                POSIX Programmer's Manual               TOLOWER(3P)
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PROLOG

6       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
7       implementation of this interface may differ (consult the  corresponding
8       Linux  manual page for details of Linux behavior), or the interface may
9       not be implemented on Linux.
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NAME

12       tolower - transliterate uppercase characters to lowercase
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SYNOPSIS

15       #include <ctype.h>
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17       int tolower(int c);
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DESCRIPTION

21       The tolower() function has as a domain a type int, the value  of  which
22       is  representable as an unsigned char or the value of EOF. If the argu‐
23       ment has any other value, the behavior is undefined. If the argument of
24       tolower()  represents  an  uppercase  letter, and there exists a corre‐
25       sponding lowercase letter  (as defined by character type information in
26       the program locale category LC_CTYPE ),  the result shall be the corre‐
27       sponding lowercase letter.  All  other  arguments  in  the  domain  are
28       returned unchanged.
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RETURN VALUE

31       Upon successful completion, tolower() shall return the lowercase letter
32       corresponding to the argument passed; otherwise, it  shall  return  the
33       argument unchanged.
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ERRORS

36       No errors are defined.
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38       The following sections are informative.
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EXAMPLES

41       None.
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APPLICATION USAGE

44       None.
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RATIONALE

47       None.
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FUTURE DIRECTIONS

50       None.
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SEE ALSO

53       setlocale(), the Base Definitions volume of IEEE Std 1003.1-2001, Chap‐
54       ter 7, Locale, <ctype.h>
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57       Portions of this text are reprinted and reproduced in  electronic  form
58       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
59       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
60       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
61       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
62       event of any discrepancy between this version and the original IEEE and
63       The Open Group Standard, the original IEEE and The Open Group  Standard
64       is  the  referee document. The original Standard can be obtained online
65       at http://www.opengroup.org/unix/online.html .
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69IEEE/The Open Group                  2003                          TOLOWER(3P)
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