1ISALNUM(P)                 POSIX Programmer's Manual                ISALNUM(P)
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NAME

6       isalnum - test for an alphanumeric character
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SYNOPSIS

9       #include <ctype.h>
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11       int isalnum(int c);
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DESCRIPTION

15       The  isalnum()  function  shall  test whether c is a character of class
16       alpha or digit in the program's current locale; see  the  Base  Defini‐
17       tions volume of IEEE Std 1003.1-2001, Chapter 7, Locale.
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19       The  c  argument  is  an  int, the value of which the application shall
20       ensure is representable as an unsigned char or equal to  the  value  of
21       the  macro  EOF.  If  the argument has any other value, the behavior is
22       undefined.
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RETURN VALUE

25       The isalnum() function shall return non-zero if c  is  an  alphanumeric
26       character; otherwise, it shall return 0.
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ERRORS

29       No errors are defined.
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31       The following sections are informative.
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EXAMPLES

34       None.
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APPLICATION USAGE

37       To  ensure  applications  portability,  especially  across natural lan‐
38       guages, only this function and those listed in  the  SEE  ALSO  section
39       should be used for character classification.
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RATIONALE

42       None.
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FUTURE DIRECTIONS

45       None.
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SEE ALSO

48       isalpha() , iscntrl() , isdigit() , isgraph() , islower() , isprint() ,
49       ispunct() , isspace() , isupper() , isxdigit() , setlocale() , the Base
50       Definitions   volume   of   IEEE Std 1003.1-2001,  Chapter  7,  Locale,
51       <ctype.h>, <stdio.h>
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54       Portions of this text are reprinted and reproduced in  electronic  form
55       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
56       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
57       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
58       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
59       event of any discrepancy between this version and the original IEEE and
60       The Open Group Standard, the original IEEE and The Open Group  Standard
61       is  the  referee document. The original Standard can be obtained online
62       at http://www.opengroup.org/unix/online.html .
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66IEEE/The Open Group                  2003                           ISALNUM(P)
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