olmstead@sri-unix (11/08/82)
I don't recall seeing this one here before, though maybe it should be sent to net.unix-wizards instead: How many of you know why plain executable unix files have a "magic number" of octal 407?
aps (11/11/82)
407 (base 8) will branch passed the a.out header on PDP-11's. aps.
CSvax:cak (11/13/82)
I do! I do! It was a number of years before I understood it... actually, I was teaching a course in pdp-11 assembler, and realized that "407" is jmp .+7 which just gets you over the 8-byte header into the code. Great for standalone objects. Cheers, chris