GCompare / GPatch - A high quality patch system for software updates
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GCompare generates patch files for the distribution of file updates.
GPatch applies the patches.

The patch file can contain patches for any number of files.
The file format is optimized for size - the patch files are very short.
CRC error checking provides safe operations.
The programs work with any type of files.

The patch files are portable. GPatch and GCompare executables are
available for some IX platforms and Windows.


Changes since last upload:

Added the PPC versions.
GCompare: Small changes in the help text.
Some changes in the guide and in the example scripts.


Changes since previous version:

GCompare: New algorithm for very high search speed (three-dimensional
search arrays). Needs more than 128 MB of memory for one patch or more
than 256 MB for additional patches. (Works of course still with fewer
memory available.)
Changed the CRC algorithm to get a comparable result with other programs.
New algorithm for Amiga executables (reloc hunk encoding) for much better
results.
Many improvements of the coding algorithms. New file format.

GPatch: Can now replace the old file and make an optional backup.

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Why should you use GCompare?
Here you have an example with different patch programs:

Let's assume, you have a new file of your program AWeb-II.
The world is using the old versions 3.2 and 3.3, and you want to
provide an update to the new version 3.4.
What you have to do is:


Build the difference files:

scompare -oAWeb32-34.spatch AWeb-II-3.2 AWeb-II-3.4
scompare -oAWeb33-34.spatch AWeb-II-3.3 AWeb-II-3.4

This needs 1:28 minutes, and you have two files:

AWeb32-34.spatch                240960 ----rwed
AWeb33-34.spatch                193328 ----rwed


or you use

gcompare AWeb-II-3.2 AWeb-II-3.3 AWeb.gpatch
gcompare AWeb-II-3.3 AWeb-II-3.4 AWeb.gpatch

This needs 0:59 minutes, and you have one file for both patches:

AWeb.gpatch                     220694 ----rwed

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Now you have to create the distribution archive. You have to add
the patcher and a script to build the new file.
For the example we leave the script out. The relevant lines of
the scripts would be:

spatch -oAWeb-II-3.4 -pAWeb32-34.spatch AWeb-II  (and for the other)
spatch -oAWeb-II-3.4 -pAWeb33-34.spatch AWeb-II
copy AWeb-II-3.4 AWeb3:AWeb-II

or

gpatch AWeb3:AWeb-II AWeb.gpatch RECURSIVE DIRECT

(This line patches both versions of the program.)

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So, let's build the archive:

lha -a a awebupdateS AWeb32-34.spatch
lha -a a awebupdateS AWeb33-34.spatch
lha -a a awebupdateS spatch

or

lha -a a awebupdateG AWeb.gpatch
lha -a a awebupdateG gpatch

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The resulting file is:

awebupdateS.lha                 277258 ----rwed

or

awebupdateG.lha                 163593 ----rwed

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]                 1926    2434  79.1% -lh5- 9147 Aug 19  2002 GPatch/bin.info
[generic]                15905   28084  56.6% -lh5- 59ca Sep  6  2002 GPatch/bin/GCompare
[generic]                13054   21448  60.9% -lh5- 13d1 Sep  6  2002 GPatch/bin/GPatch
[generic]                11393   18480  61.7% -lh5- c9f1 Nov 18  1998 GPatch/bin/old/GPatch-2.6
[generic]                 6723   11112  60.5% -lh5- e6d5 May 11  1997 GPatch/bin/old/GPatch_1.4
[generic]                 6610   10908  60.6% -lh5- 891b Jul  5  1997 GPatch/bin/old/GPatch_1.6
[generic]                27677   78756  35.1% -lh5- 0343 Sep  8  2002 GPatch/bin/PPC/GCompare.MOS
[generic]                27147   77804  34.9% -lh5- 1733 Sep  8  2002 GPatch/bin/PPC/GCompare.PUP
[generic]                16906   45696  37.0% -lh5- 20d4 Sep  8  2002 GPatch/bin/PPC/GCompare.WOS
[generic]                16883   44680  37.8% -lh5- 3266 Sep  8  2002 GPatch/bin/PPC/GPatch.MOS
[generic]                16355   43728  37.4% -lh5- b2f1 Sep  8  2002 GPatch/bin/PPC/GPatch.PUP
[generic]                11555   29560  39.1% -lh5- 8223 Sep  8  2002 GPatch/bin/PPC/GPatch.WOS
[generic]                 2871    6125  46.9% -lh5- dcbc Sep 16  2002 GPatch/ExampleScripts.info
[generic]                  833    3079  27.1% -lh5- 7ade Aug 18  2002 GPatch/ExampleScripts/CompareScript
[generic]                  285     672  42.4% -lh5- 541a Dec 24  1997 GPatch/ExampleScripts/CompareScript.info
[generic]                  377     724  52.1% -lh5- 5176 Sep 16  2002 GPatch/ExampleScripts/GCompareAdd
[generic]                 2771    5717  48.5% -lh5- 72e6 Sep 16  2002 GPatch/ExampleScripts/GCompareAdd.info
[generic]                  161     815  19.8% -lh5- 8820 Feb 28  1998 GPatch/ExampleScripts/MakePatchFile
[generic]                 2826    5781  48.9% -lh5- 0fd9 Sep 16  2002 GPatch/ExampleScripts/MakePatchFile.info
[generic]                  392     834  47.0% -lh5- b7bf Aug 18  2002 GPatch/ExampleScripts/UpdateMyProgram
[generic]                  509    1243  40.9% -lh5- 985e Aug 18  2002 GPatch/ExampleScripts/UpdateMyProgram.info
[generic]                  900    2816  32.0% -lh5- 4938 Aug 29  2002 GPatch/ExampleScripts/UpdateMyProgram.installer
[generic]                  451    1176  38.4% -lh5- f38a Nov 16  1998 GPatch/ExampleScripts/UpdateMyProgram.installer.info
[generic]                 5761   15788  36.5% -lh5- 3180 Sep 20  2002 GPatch/GPatch.guide
[generic]                 4031    6333  63.7% -lh5- 09bf Sep 20  2002 GPatch/GPatch.guide.info
[generic]                 7190   18922  38.0% -lh5- 1e8b Sep 20  2002 GPatch/GPatchD.guide
[generic]                 4066    6356  64.0% -lh5- ce55 Sep 20  2002 GPatch/GPatchD.guide.info
[generic]                 1636    3635  45.0% -lh5- afd9 Aug 19  2002 GPatch/GPatchHistory.guide
[generic]                 4377    6355  68.9% -lh5- f4c1 Aug 26  2002 GPatch/GPatchHistory.guide.info
[generic]                  260     504  51.6% -lh5- 81de Sep  9  2002 GPatch/Machines.readme
[generic]                 4092    6219  65.8% -lh5- 446c Sep 20  2002 GPatch.info
[generic]                 1245    3133  39.7% -lh5- 3526 Sep 20  2002 gpatch.readme
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        32 files  217168  508917  42.7%            Sep 22  2002