vis man page on Xenix

Man page or keyword search:  
man Server   1130 pages
apropos Keyword Search (all sections)
Output format
Xenix logo
[printable version]

VIS(3)									VIS(3)

NAME
       vis - visually encode characters

SYNOPSIS
       #include <vis.h>

       char *vis(dst, c, flag, nextc)
       char *dst, c, nextc;
       int flag;

       int strvis(dst, src, flag)
       char *dst, *src;
       int flag;

       int strvisx(dst, src, len, flag)
       char *dst, *src;
       int len, flag;

DESCRIPTION
       Vis  copies  into  dst a string which represents the character c.  If c
       needs no encoding, it is copied in unaltered.  The string is null  ter‐
       minated, and a pointer to the end of the string is returned.  The maxi‐
       mum length of any encoding is four characters (not including the trail‐
       ing  NULL);  thus, when encoding a set of characters into a buffer, the
       size of the buffer should  be  four  times  the	number	of  characters
       encoded,	 plus  one  for the trailing NULL.  The flag parameter is used
       for altering the default range of characters  considered	 for  encoding
       and  for altering the visual representation.  The additional character,
       nextc, is only used  when  selecting  the  VIS_CSTYLE  encoding	format
       (explained below).

       Strvis  and strvisx copy into dst a visual representation of the string
       src.  Strvis encodes characters from src up to the first NULL.  Strvisx
       encodes	exactly len characters from src (this is useful for encoding a
       block of data that may contain NULL's).	Both forms NULL terminate dst.
       Dst  must be four times the number of characters encoded from src (plus
       one for the NULL).  Both forms return the number of characters  in  dst
       (not including the trailing NULL).

       The  encoding is a unique, invertible representation comprised entirely
       of graphic characters; it can be decoded back into  the	original  form
       using the unvis(3) or strunvis(3) functions.

       There  are  two parameters that can be controlled: the range of charac‐
       ters that are  encoded,	and  the  type	of  representation  used.   By
       default, all non-graphic characters (see isgraph(3)) except space, tab,
       and newline are encoded.	 The following flags alter this:

       VIS_SP Also encode space.

       VIS_TAB
	      Also encode tab.

       VIS_NL Also encode newline.

       VIS_WHITE
	      Synonym for VIS_SP | VIS_TAB | VIS_NL.

       VIS_SAFE
	      Only encode "unsafe" characters.	Unsafe means  control  charac‐
	      ters  which  may	cause  common  terminals to perform unexpected
	      functions.  Currently this  form	allows	space,	tab,  newline,
	      backspace, bell, and return - in addition to all graphic charac‐
	      ters - unencoded.

       There are three forms of encoding.  All forms use the backslash charac‐
       ter  (``\'')  to introduce a special sequence; two backslashes are used
       to represent a real backslash.  These are the visual formats:

       (default)
	      Use an ``M'' to represent meta characters (characters  with  the
	      8th bit set), and use carat (``^'') to represent control charac‐
	      ters see (iscntrl(3)).  The following formats are used:

	      \^C    Represents the control character ``C''.  Spans characters
		     \000 through \037, and \177 (as \^?).

	      \M-C   Represents	 character  ``C'' with the 8th bit set.	 Spans
		     characters \241 through \376.

	      \M^C   Represents control character ``C'' with the 8th bit  set.
		     Spans characters \200 through \237, and \377 (as \M^?).

	      \040   Represents ACSII space.

	      \240   Represents Meta-space.

       VIS_CSTYLE
	      Use C-style backslash sequences to represent standard non-print‐
	      able characters.	The following sequences are used to  represent
	      the indicated characters:

	      \a   - BEL (007)
	      \b   - BS	 (010)
	      \f   - NP	 (014)
	      \n   - NL	 (012)
	      \r   - CR	 (015)
	      \t   - HT	 (011)
	      \v   - VT	 (013)
	      \0   - NUL (000)

	      When  using  this	 format,  the  nextc parameter is looked at to
	      determine if a NULL character can be encoded as  ``\0''  instead
	      of ``\000''.  If nextc is an octal digit, the latter representa‐
	      tion is used to avoid ambiguity.

       VIS_OCTAL
	      Use a three digit octal sequence.	 The form is ``\ddd'' where  d
	      represents an octal digit.

       There  is one additional flag, VIS_NOSLASH, which inhibits the doubling
       of backslashes and the backslash before the default  format  (that  is,
       control	characters  are represented by ^C and meta characters as M-C).
       With this flag set, the encoding is ambiguous and non-invertible.

SEE ALSO
       vis(1), unvis(1), unvis(3)

4.4 Berkeley Distribution	 June 23, 1990				VIS(3)
[top]
                             _         _         _ 
                            | |       | |       | |     
                            | |       | |       | |     
                         __ | | __ __ | | __ __ | | __  
                         \ \| |/ / \ \| |/ / \ \| |/ /  
                          \ \ / /   \ \ / /   \ \ / /   
                           \   /     \   /     \   /    
                            \_/       \_/       \_/ 
More information is available in HTML format for server Xenix

List of man pages available for Xenix

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net