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@(#)vis.1 1.1 (Berkeley) 05/15/90

C 7 vis - display non-printable characters in a visual format vis [ -nwcgoifsh ] [ -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. A detailed description of the various visual formats is given in cencode(3). The c, g, and o flags select a particular display format. All three can be requested independent of each other, since two of them only operate on a subset of the non-printable characters. Request a format which displays a small subset of the non-printable characters using C-style backslash sequences. Request a format which displays non-printable characters using a \\^C notation for control characters, and \\M notation for meta characters (chars with the 8th bit set). All non-printables, except space and meta-space when using the -w flag, can be encoded using this format. Request a format which displays non-printable characters as an octal number, \\ddd. All non-printable characters can be displayed using this format. Normally vis considers white space (space-tab-newline) as printable. The -w flag causes white space to be encoded in a visual form. Causes vis to invert visually encoded data back to its original form. When using -i, it is unnecessary to select an encoding format, since all formats are unique and invertible. and 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 -i. If the last character in the encoded file does not end in a newline, vis automatically appends a hidden newline to the end. This makes various editors and other utilities happy. Causes vis to strip the 8th bit on all characters. This obviously produces non-invertible output. Normally, if none of -c, -g, or -o are selected, vis turns on all three flags. The -n flag forces vis to disable any encoding, except for backslash stuffing and line length folding. When using -i to invert data, this causes vis to treat the hat (^) as a special character all the time (normally, all visual sequences are preceded by a backslash). This option is provided for compatibility with the common convention that ^C introduces a control character sequence; however, the new invertible sequence, \\^C, is recommended as the preferred representation. cencode(3)