ISBLANK (3) | C library functions | Unix Manual Pages | :man ▋
isblank - space or tab character test
Library Synopsis Description Return Values Compatibility See Also Standards
.In ctype.h int isblank "int c"
The isblank function tests for a space or tab character. For any locale, this includes the following standard characters:
In the "C" locale
isblank successful test is limited to this characters only. 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.
The isblank function returns zero if the character tests false and returns non-zero if the character tests true.
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 iswblank function should be used instead.
ctype(3), iswblank(3), multibyte(3), ascii(7)