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It was a dark and stormy night. Suddenly "Chris Gray" <chris.gray@acunia.com> began to type furiously: > Alex Schuilenburg wrote: > > > I asked the compiler folks around here. The answer I got was that > > "bss" was actually the mnemonic for the IBM/370 instruction that > > zero'ed a section of memory, and hence how the naming of the section was derived. > > > > No-one can recall what the mnemonics actually stood for though - not old enough ;-) Well, I qualify for this one ;-) Back in the olden days when everything was written in assembly language, evaluating arithmetic expressions was really hard; that's why FORTRAN originally constrained array subscripts to look like "n*k+i": you could leave out parts but if present, they must be written in this order. Anyway, writing in assembly language itself was a bit of a challenge because the assembler didn't allow expressions just anywhere. Where today, you'd write something like: MyLabel: . = . + 500 to reserve some memory, the assembler had to provide a special opcode: MyLabel bss 500 that defined "MyLabel" as a "block started by symbol" and "MyLabel" was addressed as the first location in the memory area. There was also a "BES" that was "block ended by symbol": MyLabel bes 500 that assigned "MyLabel" to the last (last + 1? I don't remember) location of the block. Thank goodness that everything is not a special case these days. Cheers! ---------------------------------------------+----------------------------- Tommy Reynolds | mailto: <reynolds@redhat.com> Red Hat, Inc., Embedded Development Services | Phone: +1.256.704.9286 307 Wynn Drive NW, Huntsville, AL 35805 USA | FAX: +1.256.837.3839 Senior Software Developer | Mobile: +1.919.641.2923
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