ISBLANK(3) Library Functions Manual ISBLANK(3)
NAME
isblankblank-space character test
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <ctype.h>
int
isblank(int c);
DESCRIPTION
The isblank() function tests for the standard blank-space characters. The standard blank-space characters are the following:
 
‘ '
Space character.
\t
Horizontal tab.
 
In the ``C'' locale, isblank() returns true only for the standard blank-space characters.
RETURN VALUES
The isblank() function returns zero if the character tests false and returns non-zero if the character tests true.
SEE ALSO
CAVEATS
The argument to isblank() must be EOF or representable as an unsigned char; otherwise, the behavior is undefined. See the CAVEATS section of ctype(3) for more details.