TARBOOT(1M)

NAME
tarboot - boot standalone programs off a tar-format tape

SYNOPSIS
/usr/mdec/tarboot

DESCRIPTION
Tarboot is a standalone bootstrap which will load a program from an (unblocked) tar-format tape on a TM11 or equivalent. When started, it prompts with `=' for a filename; it then rewinds the tape and searches it for a file of that name. The first file of that name is loaded into core and executed. The file may be either a UNIX object module compiled as neither shared-text nor split-space, or a Dec absolute-loader load module.

The most effective way to use it is to make tarboot the very first file on the tape, in which case the Dec block-1 magtape boot will load and start tarboot properly.

DIAGNOSTICS
Not many; it halts if it can't recognize the format of the file, and spins the tape forever if it can't find the file.

HISTORY
Written at U of T by Henry Spencer.

BUGS
Dec absolute-loader load modules actually aren't supported yet, although the hooks are there.

The response to tape i/o errors is simplistic.

Absolute-loader files must be stripped of leading NULs.

It assumes you have at least 56KB of memory.

Attempts to load a program larger than about 54KB will fail because tarboot will stomp itself.

It should put out a newline before the prompt.

It sure would be nice if tarboot supported command-line arguments.