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| author | Cem Keylan <cem@ckyln.com> | 2020-10-16 17:47:01 +0300 |
|---|---|---|
| committer | Cem Keylan <cem@ckyln.com> | 2020-10-16 17:47:01 +0300 |
| commit | 5d69c6a2661bba0a22f3ecfd517e2e9767a38346 (patch) | |
| tree | 1f479b2714e127835db7f33a3bfed4c38c52f883 /usr.bin/m4/NOTES | |
| parent | e2abcdca396661cbe0ae2ddb13d5c2b85682c13a (diff) | |
| download | otools-5d69c6a2661bba0a22f3ecfd517e2e9767a38346.tar.gz | |
add tools
Diffstat (limited to 'usr.bin/m4/NOTES')
| -rw-r--r-- | usr.bin/m4/NOTES | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/usr.bin/m4/NOTES b/usr.bin/m4/NOTES new file mode 100644 index 0000000..d60f80e --- /dev/null +++ b/usr.bin/m4/NOTES @@ -0,0 +1,64 @@ +m4 - macro processor + +PD m4 is based on the macro tool distributed with the software +tools (VOS) package, and described in the "SOFTWARE TOOLS" and +"SOFTWARE TOOLS IN PASCAL" books. It has been expanded to include +most of the command set of SysV m4, the standard UN*X macro processor. + +Since both PD m4 and UN*X m4 are based on SOFTWARE TOOLS macro, +there may be certain implementation similarities between +the two. The PD m4 was produced without ANY references to m4 +sources. + +written by: Ozan S. Yigit + +References: + + Software Tools distribution: macro + + Kernighan, Brian W. and P. J. Plauger, SOFTWARE + TOOLS IN PASCAL, Addison-Wesley, Mass. 1981 + + Kernighan, Brian W. and P. J. Plauger, SOFTWARE + TOOLS, Addison-Wesley, Mass. 1976 + + Kernighan, Brian W. and Dennis M. Ritchie, + THE M4 MACRO PROCESSOR, Unix Programmer's Manual, + Seventh Edition, Vol. 2, Bell Telephone Labs, 1979 + + System V man page for M4 + + +Implementation Notes: + +[1] PD m4 uses a different (and simpler) stack mechanism than the one + described in Software Tools and Software Tools in Pascal books. + The triple stack thing is replaced with a single stack containing + the call frames and the arguments. Each frame is back-linked to a + previous stack frame, which enables us to rewind the stack after + each nested call is completed. Each argument is a character pointer + to the beginning of the argument string within the string space. + The only exceptions to this are (*) arg 0 and arg 1, which are + the macro definition and macro name strings, stored dynamically + for the hash table. + + . . + | . | <-- sp | . | + +-------+ +-----+ + | arg 3 ------------------------------->| str | + +-------+ | . | + | arg 2 --------------+ . + +-------+ | + * | | | + +-------+ | +-----+ + | plev | <-- fp +---------------->| str | + +-------+ | . | + | type | . + +-------+ + | prcf -----------+ plev: paren level + +-------+ | type: call type + | . | | prcf: prev. call frame + . | + +-------+ | + | <----------+ + +-------+ |