VIS(1)                  System General Commands Manual                  VIS(1)

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

SYNOPSIS
     vis [-cbflnostw] [-F foldwidth] [file ...]

DESCRIPTION
     vis is a filter for converting non-printable characters into a visual
     representation.  It differs from cat -v in that the form can be unique
     and invertible.  By default, all non-printing characters except space,
     tab, and newline are encoded, as are any meta-characters (eighth bit
     set).  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
             sequences and meta-characters, and disables the doubling of back-
             slashes.  This produces output which is neither invertible nor
             precise, but does represent a minimum of change to the input.  It
             is similar to cat -v.

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

     -F foldwidth
             Causes vis to fold output lines to foldwidth columns, 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 lines.

     -f      Like -F, except output is always folded to 80 columns.

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

     -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.

     -s      Only characters considered unsafe to send to a terminal are
             encoded.  This flag allows backspace, bell, and carriage return
             in addition to the default space, tab, and newline.  Meta-charac-
             ters that are considered graphic characters by isgraph(3) are not
             encoded.

     -t      Tabs are also encoded.

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

SEE ALSO
     unvis(1), vis(3)

HISTORY
     The vis command appeared in 4.4BSD.

Interix                          May 29, 2007                          Interix