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VIS(1)			  BSD General Commands Manual			VIS(1)

     vis -- display non-printable characters in	a visual format

     vis [-bcfhlmnostw]	[-e extra] [-F foldwidth] [file	...]

     vis is a filter for converting non-printable characters into a visual
     representation.  It differs from `cat -v' in that the form	is unique and
     invertible.  By default, all non-graphic characters except	space, tab,
     and newline are encoded.  A detailed description of the various visual
     formats is	given in vis(3).

     The options are as	follows:

     -b	     Turns off prepending of backslash before up-arrow control se-
	     quences and meta characters, and disables the doubling of back-
	     slashes.  This produces output which is neither invertible	or
	     precise, but does represent a minimum of change to	the input.  It
	     is	similar	to "cat	-v".  (VIS_NOSLASH)

     -c	     Request a format which displays a small subset of the non-print-
	     able characters using C-style backslash sequences.	 (VIS_CSTYLE)

     -e	extra
	     Also encode characters in extra, per svis(3).

     -F	foldwidth
	     Causes vis	to fold	output lines to	foldwidth columns (default
	     80), like fold(1),	except that a hidden newline sequence is used,
	     (which is removed when inverting the file back to its original
	     form with unvis(1)).  If the last character in the	encoded	file
	     does not end in a newline,	a hidden newline sequence is appended
	     to	the output.  This makes	the output usable with various editors
	     and other utilities which typically don't work with partial

     -f	     Same as -F.

     -h	     Encode using the URI encoding from	RFC 1808.  (VIS_HTTPSTYLE)

     -l	     Mark newlines with	the visible sequence `\$', followed by the

     -m	     Encode using the MIME Quoted-Printable encoding from RFC 2045.

     -n	     Turns off any encoding, except for	the fact that backslashes are
	     still doubled and hidden newline sequences	inserted if -f or -F
	     is	selected.  When	combined with the -f flag, vis becomes like an
	     invertible	version	of the fold(1) utility.	 That is, the output
	     can be unfolded by	running	the output through unvis(1).

     -o	     Request a format which displays non-printable characters as an
	     octal number, \ddd.  (VIS_OCTAL)

     -s	     Only characters considered	unsafe to send to a terminal are en-
	     coded.  This flag allows backspace, bell, and carriage return in
	     addition to the default space, tab	and newline.  (VIS_SAFE)

     -t	     Tabs are also encoded.  (VIS_TAB)

     -w	     White space (space-tab-newline) is	also encoded.  (VIS_WHITE)

     vis supports multibyte character input.  The encoding conversion is in-
     fluenced by the setting of	the LC_CTYPE environment variable which	de-
     fines the set of characters that can be copied without encoding.

     When 8-bit	data is	present	in the input, LC_CTYPE must be set to the cor-
     rect locale or to the C locale.  If the locales of	the data and the con-
     version are mismatched, multibyte character recognition may fail and en-
     coding will be performed byte-by-byte instead.

     LC_CTYPE  Specify the locale of the input data.  Set to C if the input
	       data locale is unknown.

     unvis(1), svis(3),	vis(3)

     The vis command appears in	4.4BSD.	 Myltibyte character support was added
     in	NetBSD 6.1 and FreeBSD 9.2.

BSD			       February	13, 2013			   BSD


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