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$ man xxd
XXD(1) General Commands Manual XXD(1)
NAME
xxd - make a hexdump or do the reverse.
SYNOPSIS
xxd -h[elp]
xxd [options] [infile [outfile]]
xxd -r[evert] [options] [infile [outfile]]
DESCRIPTION
xxd creates a hex dump of a given file or stan‐
dard input. It can also convert a hex dump back
to its original binary form. Like uuencode(1)
and uudecode(1) it allows the transmission of
binary data in a `mail-safe' ASCII representa‐
tion, but has the advantage of decoding to stan‐
dard output. Moreover, it can be used to perform
binary file patching.
OPTIONS
If no infile is given, standard input is read.
If infile is specified as a `-' character, then