166827Sbostic.\" Copyright (c) 1989, 1991, 1993, 1994 262427Sbostic.\" The Regents of the University of California. All rights reserved. 341960Smarc.\" 448326Sbostic.\" %sccs.include.redist.roff% 541960Smarc.\" 6*66926Sbostic.\" @(#)vis.1 8.4 (Berkeley) 04/19/94 741960Smarc.\" 848593Scael.Dd 948593Scael.Dt VIS 1 1058795Scael.Os BSD 4.4 1148593Scael.Sh NAME 1248593Scael.Nm vis 1348593Scael.Nd display non-printable characters in a visual format 1448593Scael.Sh SYNOPSIS 1548593Scael.Nm vis 1648593Scael.Op Fl cbflnostw 1748593Scael.Op Fl F Ar foldwidth 1848593Scael.Op Ar file ... 1948593Scael.Sh DESCRIPTION 2048593Scael.Nm Vis 2148593Scaelis a filter for converting non-printable characters 2248593Scaelinto a visual representation. It differs from 2348593Scael.Ql cat -v 2448593Scaelin that 2544589Smarcthe form is unique and invertible. By default, all non-graphic 2644589Smarccharacters except space, tab, and newline are encoded. 2744589SmarcA detailed description of the 2848593Scaelvarious visual formats is given in 2948593Scael.Xr vis 3 . 3048593Scael.Pp 3166827SbosticThe options are as follows: 3248593Scael.Bl -tag -width Ds 3348593Scael.It Fl b 3448593ScaelTurns off prepending of backslash before up-arrow control sequences 3548593Scaeland meta characters, and disables the doubling of backslashes. This 3648593Scaelproduces output which is neither invertible or precise, but does 3748593Scaelrepresent a minimum of change to the input. It is similar to 3848593Scael.Dq Li cat -v . 3948593Scael.It Fl c 4041960SmarcRequest a format which displays a small subset of the 4141960Smarcnon-printable characters using C-style backslash sequences. 4248593Scael.It Fl F 4341960SmarcCauses 4448593Scael.Nm vis 4548593Scaelto fold output lines to foldwidth columns (default 80), like 4648593Scael.Xr fold 1 , 4748593Scaelexcept 4844589Smarcthat a hidden newline sequence is used, (which is removed 4948593Scaelwhen inverting the file back to its original form with 5048593Scael.Xr unvis 1 ) . 5141960SmarcIf the last character in the encoded file does not end in a newline, 5244589Smarca hidden newline sequence is appended to the output. 5344589SmarcThis makes 5466883Sbosticthe output usable with various editors and other utilities which 5544589Smarctypically don't work with partial lines. 5648593Scael.It Fl f 5748593ScaelSame as 5848593Scael.Fl F . 5948593Scael.It Fl l 60*66926SbosticMark newlines with the visible sequence 6148593Scael.Ql \e$ , 6248593Scaelfollowed by the newline. 6348593Scael.It Fl n 6444589SmarcTurns off any encoding, except for the fact that backslashes are 6548593Scaelstill doubled and hidden newline sequences inserted if 6648593Scael.Fl f 6748593Scaelor 6848593Scael.Fl F 6948593Scaelis selected. When combined with the 7048593Scael.Fl f 7148593Scaelflag, 7248593Scael.Nm vis 7348593Scaelbecomes like 7448593Scaelan invertible version of the 7548593Scael.Xr fold 1 7648593Scaelutility. That is, the output 7748593Scaelcan be unfolded by running the output through 7848593Scael.It Fl o 7948593ScaelRequest a format which displays non-printable characters as 8048593Scaelan octal number, \eddd. 8148593Scael.It Fl s 8248593ScaelOnly characters considered unsafe to send to a terminal are encoded. 8348593ScaelThis flag allows backspace, bell, and carriage return in addition 8448593Scaelto the default space, tab and newline. 8548593Scael.Xr unvis 1 . 8648593Scael.It Fl t 8748593ScaelTabs are also encoded. 8848593Scael.It Fl w 8948593ScaelWhite space (space-tab-newline) is also encoded. 9048593Scael.El 9148593Scael.Sh SEE ALSO 9266827Sbostic.Xr unvis 1 , 9348593Scael.Xr vis 3 9448593Scael.Sh HISTORY 9548593ScaelThe 9648593Scael.Nm 9758795Scaelcommand appears in 9858795Scael.Bx 4.4 . 99