rshasum is a recursive SHA sum program.
A SHA algorithm may be specified with the -a flag; valid algorithms
are 1, 256, 384, and 512; these select SHA-1, SHA-256, SHA-384, and
SHA-512, respectively. The default is SHA-256.
Typically, hidden (dot) files are skipped. For example, given the following directory tree
testdir/
├── .hidden
└── file
the .hidden file will not be hashed. The -d flag (for dotfiles)
will cause rshasum to hash these files.
To compare a digest file, the -c flag should be used. In this
case, the file arguments are taken to be files containing digests
and filenames. While it can match the standard shasum format for
text files, it will not recognise portable or binary file formats.
It will also recognise the OpenBSD sha digest utilities, provided
they were called in reverse format (ex. sha1 -r).
Copyright (c) 2014 Kyle Isom kyle@tyrfingr.is
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