1ISALPHA(P) POSIX Programmer's Manual ISALPHA(P)
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6 isalpha - test for an alphabetic character
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9 #include <ctype.h>
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11 int isalpha(int c);
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15 The isalpha() function shall test whether c is a character of class
16 alpha in the program's current locale; see the Base Definitions volume
17 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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25 The isalpha() function shall return non-zero if c is an alphabetic
26 character; otherwise, it shall return 0.
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29 No errors are defined.
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31 The following sections are informative.
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34 None.
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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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42 None.
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45 None.
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48 isalnum() , 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 ISALPHA(P)