diff options
Diffstat (limited to 'lib/libc/gen/unvis.3')
| -rw-r--r-- | lib/libc/gen/unvis.3 | 55 |
1 files changed, 30 insertions, 25 deletions
diff --git a/lib/libc/gen/unvis.3 b/lib/libc/gen/unvis.3 index c3a8de70fa2..fd2eb9976c3 100644 --- a/lib/libc/gen/unvis.3 +++ b/lib/libc/gen/unvis.3 @@ -1,4 +1,4 @@ -.\" $OpenBSD: unvis.3,v 1.5 1999/05/16 19:55:02 alex Exp $ +.\" $OpenBSD: unvis.3,v 1.6 1999/05/29 22:38:36 aaron Exp $ .\" .\" Copyright (c) 1989, 1991, 1993 .\" The Regents of the University of California. All rights reserved. @@ -54,36 +54,38 @@ are used to decode a visual representation of characters, as produced by the .Xr vis 3 function, back into -the original form. Unvis is called with successive characters in -.Ar c +the original form. +.Fn unvis +is called with successive characters in +.Fa c until a valid sequence is recognized, at which time the decoded character is available at the character pointed to by -.Ar cp . -Strunvis decodes the -characters pointed to by -.Ar src +.Fa cp . +.Pp +.Fn strunvis +decodes the characters pointed to by +.Fa src into the buffer pointed to by -.Ar dst . +.Fa dst . .Pp The .Fn strunvis function simply copies -.Ar src +.Fa src to -.Ar dst , +.Fa dst , decoding any escape sequences along the way, and returns the number of characters placed into -.Ar dst , -or \-1 if an +.Fa dst , +or -1 if an invalid escape sequence was detected. The size of -.Ar dst +.Fa dst should be equal to the size of -.Ar src -(that is, no expansion takes place during -decoding). +.Fa src +(that is, no expansion takes place during decoding). .Pp The .Fn unvis @@ -100,23 +102,25 @@ to zero. Call with each successive byte, along with a pointer to this integer, and a pointer to a destination character. The -.Xr unvis +.Fn unvis function has several return codes that must be handled properly. They are: .Bl -tag -width UNVIS_VALIDPUSH .It Li \&0 (zero) Another character is necessary; nothing has been recognized yet. -.It Dv UNVIS_VALID +.It Dv UNVIS_VALID A valid character has been recognized and is available at the location -pointed to by cp. -.It Dv UNVIS_VALIDPUSH +pointed to by +.Fa cp . +.It Dv UNVIS_VALIDPUSH A valid character has been recognized and is available at the location -pointed to by cp; however, the character currently passed in should -be passed in again. -.It Dv UNVIS_NOCHAR +pointed to by +.Fa cp ; +however, the character currently passed in should be passed in again. +.It Dv UNVIS_NOCHAR A valid sequence was detected, but no character was produced. This return code is necessary to indicate a logical break between characters. -.It Dv UNVIS_SYNBAD +.It Dv UNVIS_SYNBAD An invalid escape sequence was detected, or the decoder is in an unknown state. The decoder is placed into the starting state. .El @@ -127,6 +131,7 @@ one more time with flag set to .Dv UNVIS_END to extract any remaining character (the character passed in is ignored). .Pp +.Sh EXAMPLES The following code fragment illustrates a proper use of .Fn unvis . .Bd -literal -offset indent @@ -159,6 +164,6 @@ if (unvis(&out, (char)0, &state, UNVIS_END) == UNVIS_VALID) .Xr vis 3 .Sh HISTORY The -.Nm unvis +.Fn unvis function first appeared in .Bx 4.4 . |