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(sharutils.info)Transmission

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Protecting against transmission errors
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   Transmission of shell archives is not always free of errors.  So one
should make consistency checks on the receiving site.  A very simple
(and unreliable) method is running the UNIX `wc' tool on the output
file.  This can report the number of characters in the file.

   As one can guess this does not catch all errors.  Especially
changing of a character value does not change the computed check sum.
To achieve this goal better method were invented and standardized.  One
very strong is MD5 (MD = message digests).  This is standardized in RFC
1321.  The produced shell scripts do not force the `md5sum' program to
be installed on the system.  This is necessary because it is not yet
part of every UNIX.  The program is however not necessary for producing
the shell archive.

`-w'
`--no-character-count'
     Do _not_ check with `wc -c' after unpack.  The default is to check.

`-D'
`--no-md5-digest'
     Do _not_ check with `md5sum' after unpack.  The default is to
     check.

`-F'
`--force-prefix'
     Prepend the prefix character to every line even if not required.
     This option may slightly increase the size of the archive,
     especially if `-B' or `-Z' is used.  Normally, the prefix character
     is `X'.  If the parameter to the `-d' option starts with `X', then
     the prefix character becomes `Y'.

`-d STRING'
`--here-delimiter=STRING'
     Use STRING to delimit the files in the shar instead of `SHAR_EOF'.
     This is for those who want to personalize their shar files.