isblank(3) on FreeBSD
The text d341d56e6a9b, as FreeBSD 2.2.2-RELEASE, FreeBSD 2.1.7.1-RELEASE, FreeBSD 2.1.7-RELEASE, FreeBSD 2.1.5-RELEASE, FreeBSD 2.0.5-RELEASE shipped it.
space or tab character test
The text d341d56e6a9b, as FreeBSD 2.2.2-RELEASE, FreeBSD 2.1.7.1-RELEASE, FreeBSD 2.1.7-RELEASE, FreeBSD 2.1.5-RELEASE, FreeBSD 2.0.5-RELEASE shipped it.
space or tab character test