command line syntax

[Tom M. <tme...@vl...>]

The command line is specified as:

        rsyncrypto [options] srcfile dstfile keyfile key

which seems a little bit awkward, as the 3rd argument is sort of 
optional, but the 4rd is required. It also interleaves input and output 
files. I'd suggest:

        rsyncrypto [options] pubkeyfile srcfile dstfile

with encryption examples looking like:
        rsyncrypto pubkeyfile srcfile dstfile
        rsyncrypto --key=symkeyfile pubkeyfile srcfile dstfile
        rsyncrypto -r pubkeyfile srcdir dstdir
        rsyncrypto -r --key=symkeydir pubkeyfile srcdir dstdir
        rsyncrypto --filelist pubkeyfile listfile dstdir

and decryption examples looking like:
        rsyncrypto -d prvkeyfile|symkeyfile srcfile dstfile
        rsyncrypto -d -r prvkeyfile|symkeydir srcdir dstdir

Because only one of the two key files is needed, things get a bit messy. 
In the second case, it's easy enough to distinguish a file from a 
directory, but can you distinguish an rsyncrypto generated key from a 
public key? (Should be doable. One is binary.)

Another approach might be to use named parameters for everything:

        rsyncrypto --pk=pubkeyfile --if=srcfile --of=dstfile

which is more cumbersome to type, but makes parameters position 
independent and makes it cleaner to handle things like decryption and 
the --filelist parameter:

        rsyncrypto -d --pk=pubkeyfile --filelist=listfile --of=dstdir

  -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
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