NAME
isblank —
space or tab character test
LIBRARY
library “libc”
SYNOPSIS
#include
<ctype.h>
int
isblank(int
c);
int
isblank_l(int
c, locale_t
loc);
DESCRIPTION
Theisblank()
function tests for a space or tab character. For any locale, this includes the
following standard characters:
| “\t” | “ ” |
In the "C" locale, a successful
isblank()
test is limited to these characters only. The value of the argument must be
representable as an unsigned char or the value of
EOF.
The
isblank_l()
function takes an explicit locale argument, whereas the
isblank() function uses the current global or
per-thread locale.
RETURN VALUES
The isblank() function returns zero if the
character tests false and returns non-zero if the character tests true.
COMPATIBILITY
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 iswblank()
function should be used instead.
SEE ALSO
STANDARDS
The isblank() function conforms to
ISO/IEC 9899:1999 (“ISO C99”).
The isblank_l() function conforms to
IEEE Std 1003.1-2008 (“POSIX.1”).