getty flavours from the past

getty is largely a thing of the past. It has been obsolete in AT&T Unix and its descendents since 1988, having long since been superseded by ttymon and its ilk. Even on platforms that are decades behind AT&T Unix, it has in some cases been superseded by a few simpler chain-loading tools in some system management toolsets. Here are some of its historical flavours.

There was a program named getty in 1st Edition Unix. The BSDs still usually have a program named getty that is a (fairly) direct descendant of the old Unix program. It (nowadays) reads /etc/ttys for the database of configured terminal devices and /etc/gettytab for the database of terminal line types (a line type being passed as an argument to the getty program).

The Linux world, also decades behind AT&T Unix, has a collection of clones and reimplementations of getty, as did minix before it. Depite not even coming into existence until well after getty was obsolete, the Linux and minix worlds did not clone or reimplement the more modern mechanisms of contemporary Unix.

ngetty was the closest in concept to the 1988 ttymon, although ttymon was a part of an overall larger framework, the Service Access Facility, and formed part of a regular pattern with other tools, which ngetty does not.

mingetty likewise demonstrates that when it comes to virtual terminals, almost all of the functionality of getty (a large part of which in traditional form deals with serial port mechanics, modems, terminal classes, and connection mechanisms other than interactive shells) is extraneous. Virtual terminal login via the nosh Toolset replaces it entirely, with five small chain-loading tools.

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