ISDIGIT(3) BSD Library Functions Manual ISDIGIT(3)

NAME
     iissddiiggiitt,, iissnnuummbbeerr - decimal-digit character test

LLIIBBRRAARRYY
     Standard C Library (libc, -lc)

SYNOPSIS
     ##iinncclluuddee <>

     int
     iissddiiggiitt(int c);

     int
     iissnnuummbbeerr(int c);

DESCRIPTION
     The iissddiiggiitt() function tests for a decimal digit character.  Regardless
     of locale, this includes the following characters only:

     ``0''         ``1''         ``2''         ``3''         ``4''
     ``5''         ``6''         ``7''         ``8''         ``9''

     The iissnnuummbbeerr() function behaves similarly to iissddiiggiitt(), but may recognize
     additional characters, depending on the current locale setting.

     For single C chars locales (see multibyte(3)) the value of the argument
     is representable as an unsigned char or the value of EOF.

RETURN VALUES
     The iissddiiggiitt() and iissnnuummbbeerr() functions return zero if the character tests
     false and returns non-zero if the character tests true.

CCOOMMPPAATTIIBBIILLIITTYY
     The 4.4BSD extension of accepting arguments outside of the range of the
     unsigned char type in locales with large character sets is considered
     obsolete and may not be supported in future releases.  The iisswwddiiggiitt()
     function should be used instead.

SEE ALSO
     ctype(3), iswdigit(3), multibyte(3), ascii(7), isalnuml

STANDARDS     The iissddiiggiitt() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

HISTORY     The iissnnuummbbeerr() function appeared in 4.4BSD.

BSD                             August 21, 2004                            BSD