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ISDIGIT(3)                 Library Functions Manual                 ISDIGIT(3)

NAME
     isdigit - decimal-digit character test

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     isdigit(int c);

DESCRIPTION
     The isdigit() function tests for any decimal-digit character.

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

SEE ALSO
     ctype(3), isalnum(3), isalpha(3), isascii(3), isblank(3), iscntrl(3),
     isgraph(3), islower(3), isprint(3), ispunct(3), isspace(3), isupper(3),
     isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7)

STANDARDS
     The isdigit() function conforms to ANSI X3.159-1989 ("ANSI C89").

CAVEATS
     The argument to isdigit() must be EOF or representable as an unsigned
     char; otherwise, the behavior is undefined.  See the CAVEATS section of
     ctype(3) for more details.

NetBSD 10.99                    April 17, 2008                    NetBSD 10.99