Libptytty is a small library that offers pseudo-tty management in an
OS-independent way. It was created out of frustration over the many differences
of pty/tty handling in different operating systems for the use inside
"rxvt-unicode".

In addition to offering mere pty/tty management, it also offers session database
support (utmp and optional wtmp/lastlog updates for login shells).

It also supports fork'ing after startup and dropping privileges in the calling
process, so in case the calling process gets compromised by the user starting
the program there is less to gain, as only the helper process runs with
privileges (e.g. setuid/setgid), which reduces the area of attack immensely.

Libptytty is written in C++, but it also offers a C-only API.