:man| Alphabetical   Categories   About us 
 
ISDIGIT (3) | C library functions | Unix Manual Pages | :man

NAME

isdigit, isnumber - decimal-digit character test

CONTENTS

Library
Synopsis
Description
Return Values
Compatibility
See Also
Standards
History

LIBRARY


.Lb libc

SYNOPSIS


.In ctype.h int isdigit "int c" int isnumber "int c"

DESCRIPTION

The isdigit 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 isnumber function behaves similarly to isdigit, but may recognize additional characters, depending on the current locale setting.

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

RETURN VALUES

The isdigit and isnumber functions return zero if the character tests false and returns non-zero if the character tests true.

COMPATIBILITY

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

SEE ALSO

ctype(3), iswdigit(3), multibyte(3), ascii(7)

STANDARDS

HISTORY


Share this page

     Follow us

Facebook Twitter Google+ LinkedIn


 
Created by Blin Media, 2008-2013