Ravenbrook / Projects / Memory Pool System / Version 1.111 Product Sources / Design Documents

Memory Pool System Project

             THE DESIGN OF THE MEMORY POOL SYSTEM SIGNATURE SYSTEM
                                 design.mps.sig
                               incomplete design
                               richard 1995-08-25

    TESTING:

    .test.uniq: The unix command
    sed -n '/^#define [a-zA-Z]*Sig/s/[^(]*(/(/p' *.[ch]| sort| uniq -c
    will display all signatures defined in the mps along with a count of how many
    times they are defined.  If any counts are greater than 1, then the same
    signature value is being used for different signatures.  This is undesirable
    and the problem should be investigated.  People not using unix may still find
    the RE useful.

    TEXT:

    Signatures are magic numbers which are written into structures
    when they are created and invalidated (by overwriting with
    SigInvalid) when they are destroyed.  They provide a limited form
    of run-time type checking and dynamic scope checking.

    Signature values should be transliterations of the corresponding words into
    hex, as guide.hex.trans.  The first three hex digits should be the
    transliteration of "SIG".

Note: for the transliterations, see guide.hex.trans (not currently available outside Ravenbrook).

## A. References

## B. Document History

2002-06-07 | RB | Converted from MMInfo database design document.
2009-01-27 | RHSK | Link to guide.hex.trans.

## C. Copyright and License

This document is copyright © 1995-2002 Ravenbrook Limited. All rights reserved. This is an open source license. Contact Ravenbrook for commercial licensing options.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

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Ravenbrook / Projects / Memory Pool System / Version 1.111 Product Sources / Design Documents