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In the command line, 7zip has the command 'a' to "Add files to archive". But I want to sync the files instead. This is one of the main options in the GUI, but the CLI has disregarded it for some reason.

How can I do this? Example appreciated.

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up vote 6 down vote accepted

Using some info I found online, I figured out that -uq0 is the switch you probably want. Here's an example of an update script I just tested out based on this:

"C:\Program Files\7-Zip\7z.exe" u "C:\Users\dane\Documents\Docz.7z" -uq0 "C:\Users\dane\Documents\*" -r -x!*.7z -ssw -ms=off

I tested this out and it removed a file from the archive after I deleted the file.

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Ah that did the trick! I previously saw that page, but next to "Synchronize", it says set p to 1, q to 0, r to 2, x to 1 etc. etc. (i.e. "-u-p1q0r2x1y2z1w2" - which I tried and it didn't work). I'm not sure how you interpreted the seemingly cryptic description so well. – Dan W Jan 4 '13 at 21:09
Actually, you had it right, except you inserted an extra dash in "-u-p1q0r2x1y2z1w2". If you had just used "-up1q0r2x1y2z1w2" instead, you would've been good, I believe. That dash in "-u-" apparently disables updates to the base archive, which would totally negate my example line if included. My example of "u -uq0" is identical to "u -up1q0r2x1y2z1w2", because only the "q0" is different from what "u" usually does. – Dane Jan 4 '13 at 21:16
Great that explains it all, and makes perfect sense. Thanks a lot! – Dan W Jan 4 '13 at 21:32

Use the 'u' operator (update)

Slightly edited snippit from a backup job I run:

7z.exe u Documents.7z ".\Documents\*" -r -x!*.7z -x!*.pst -t7z -ssw -mx=3 -m3=LZMA2 -mmt=2 
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Simply using 'u' doesn't sync, as files which are in the archive which aren't in the original files/folder anymore aren't deleted. – Dan W Jan 4 '13 at 18:53

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