Patch to add resume feature to scp

Girish Venkatachalam girish1729 at
Wed May 10 19:34:30 EST 2006

Sorry folks, there was a nasty merge issue and hence my previous patch
was broken.

Please bear with me for the oversight.

Here is the correct patch.


On 5/10/06, Girish Venkatachalam <girish1729 at> wrote:
> Dear all,
> I have enhanced scp to do the following.
> 1) Check the SHA1 checksums of the file fragments at the source and
> destination and resume  file transfer from where it left off last time
> 2) If the file checksums match and size also matches, then the file is
> assumed to be identical and skipped, the user is also informed of the
> same
> 3) If the destination file size is larger than the source, it is
> overwritten(conforms to prev behavior, the enhancement here being that
> checksum computation is short circuited)
> 4) If the checksums do not match for the fragment, then the file is overwritten
> 5) All the above works well in recursive mode also, the identical
> files are skipped, broken transfers resumed and all other times files
> are transferred like before
> 6) One important feature of this enhancement is that if the same file
> is not found at the destination , then the previous wire protocol is
> preserved, thus there would be no version mismatch problem for fresh
> transfers.
> However these changes do necessitate a bump in the version number
> IMHO. I could not think of any other way to solve this problem.
> I will only be too glad to make whatever changes are necessary to
> apply this patch to HEAD.
> Hope you like this work. :-)
> regards,
> Girish

Whenever people agree with me I feel I am wrong.  -- Oscar Wilde

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