Page 74
| _xsuffixes | Uses suffixes to characterize RCS files. See ci(1) for details. |
| _zzone | Specifies the date output format in keyword substitution, and specifies the default time zone for date in the _ddate option. The zone should be empty, a numeric UTC offset, or the special string LT for local time. The default is an empty zone, which uses the traditional RCS format of UTC without any time zone indication and with slashes separating the parts of the date; otherwise, times are output in ISO 8601 format with time zone indication. For example, if local time is January 11, 1990, 8 p.m. Pacific Standard Time, eight hours west of UTC, then the time is output as follows: |
| Option | Time Output |
| _z | 1990/01/12 04:00:00 (default) |
| _zLT | 1990-01-11 20:00:00_08 |
| _z+05:30 | 1990-01-12 09:30:00+05:30 |
The _z option does not affect dates stored in RCS files, which are always UTC.
KEYWORD SUBSTITUTION
Strings of the form $ keyword $ and $ keyword : ... $ embedded in the text are replaced with strings of the form $ keyword : value $, where keyword and value are pairs in the following list. Keywords can be embedded in literal strings or comments to identify a revision.
Initially, the user enters strings of the form $keyword$. On checkout, co replaces these strings with strings of the form $keyword : value$. If a revision containing strings of the latter form is checked back in, the value fields will be replaced during the next checkout. Thus, the keyword values are automatically updated on checkout. This automatic substitution can be modified by the _k options.
Keywords and their corresponding values:
| $Author$ | The login name of the user who checked in the revision. |
| $Date$ | The date and time the revision was checked in. With _zzone, a numeric time zone offset is appended; otherwise, the date is UTC. |
| $Header$ | A standard header containing the full pathname of the RCS file, the revision number, the date and time, the author, the state, and the locker (if locked). With _zzone, a numeric time zone offset is appended to the date; otherwise, the date is UTC. |
| $Id$ | Same as $Header$, except that the RCS filename is without a path. |
| $Locker$ | The login name of the user who locked the revision (empty if not locked). |
| $Log$ | The log message supplied during checkin, preceded by a header containing the RCS filename, the revision number, the author, and the date and time. With _zzone a numeric time zone offset is appended; otherwise, the date is UTC. Existing log messages are not replaced. Instead, the new log message is inserted after $Log: ... $ . This is useful for accumulating a complete change log in a source file. |
Each inserted line is prefixed by the string that prefixes the $Log$ line. For example, if the $Log$ line is // $Log: tan.cc $, RCS prefixes each line of the log with //. This is useful for languages with comments that go to the end of the line. The convention for other languages is to use a * prefix inside a multiline comment. For example, the initial log comment of a C program conventionally is of the following form:
/* * $Log$ */
For backwards compatibility with older versions of RCS, if the log prefix is /* or (* surrounded by optional whitespace, inserted log lines contain a space instead of / or (; however, this usage is obsolescent and should not be relied on.
| $Name$ | The symbolic name used to check out the revision, if any. For example, co -r Joe generates $Name: Joe $. Plain co generates just $Name: $. |
Page 75
| $RCSfile$ | The name of the RCS file without a path. |
| $Revision$ | The revision number assigned to the revision. |
| $Source$ | The full pathname of the RCS file. |
| $State$ | The state assigned to the revision with the _s option of rcs(1) or ci(1). |
The following characters in keyword values are represented by escape sequences to keep keyword strings well-formed.
| Character | Escape Sequence |
| tab | \t |
| newline | \n |
| space | \040 |
| $ | \044 |
| \ | \\ |
FILE MODES
The working file inherits the read and execute permissions from the RCS file. In addition, the owner write permission is turned on, unless _kv is set or the file is checked out unlocked and locking is set to strict; see rcs(1).
If a file with the name of the working file exists already and has write permission, co aborts the checkout, asking beforehand if possible. If the existing working file is not writable or _f is given, the working file is deleted without asking.
FILES
co accesses files much as ci(1) does, except that it does not need to read the working file unless a revision number of $ is specified.
ENVIRONMENT
RCSINIT Options prepended to the argument list, separated by spaces. See ci(1) for details.
DIAGNOSTICS
The RCS pathname, the working pathname, and the revision number retrieved are written to the diagnostic output. The exit status is zero if and only if all operations were successful.
IDENTIFICATION
Author: Walter F. Tichy.
Manual Page Revision: 5.13; Release Date: 1995/06/01.
Copyright " 1982, 1988, 1989 Walter F. Tichy.
Copyright " 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
SEE ALSO
rcsintro(1), ci(1), ctime(3), date(1), ident(1), make(1), rcs(1), rcsclean(1), rcsdiff(1), rc-smerge(1), rlog(1), rcsfile(5)
Walter F. Tichy, "RCS—A System for Version Control," Software Practice & Experience 15, 7 (July 1985), 637-654.
LIMITS
Links to the RCS and working files are not preserved.
There is no way to selectively suppress the expansion of keywords, except by writing them differently. In nroff and troff, this is done by embedding the null-character \& into the keyword.
GNU, 1 June 1995
Page 76
col—Filter reverse line feeds from input
SYNOPSIS
col [-bfx] [-l num]
DESCRIPTION
col filters out reverse (and half-reverse) line feeds so the output is in the correct order with only forward and half-forward line feeds, and replaces whitespace characters with tabs where possible. This can be useful in processing the output of nroff(1) and tbl(1). col reads from standard input and writes to standard output.
The options are as follows:
| -b | Do not output any backspaces, printing only the last character written to each column position. |
| -f | Forward half-line feeds are permitted (fine mode). Normally characters printed on a half-line boundary are printed on the following line. |
| -x | Output multiple spaces instead of tabs. |
| -lnum | Buffer at least num lines in memory. By default, 128 lines are buffered. |
The control sequences for carriage motion that col understands and their decimal values are listed in the following table:
| Control Sequence | Decimal Value |
| Esc+7 | Reverse line feed (escape then 7) |
| Esc+8 | Half-reverse line feed (escape then 8) |
| Esc+9 | Half-forward line feed (escape then 9) |
| Backspace | Moves back one column (8); ignored in the first column |
| Carriage return | (13) |
| Newline | Forward line feed (10); also does carriage return |
| Shift in | Shift to normal character set (15) |
| Shift out | Shift to alternate character set (14) |
| Space | Moves forward one column (32) |
| Tab | Moves forward to next tab stop (9) |
| Vertical tab | Reverse line feed (11) |
All unrecognized control characters and escape sequences are discarded.
col keeps track of the character set as characters are read and makes sure the character set is correct when they are output.
If the input attempts to back up to the last flushed line, col will display a warning message.
SEE ALSO
expand(1), nroff(1), tbl(1)
HISTORY
A col command appeared in version 6 AT&T UNIX.
17 June 1991
Page 77
colcrt—Filter nroff output for CRT previewing
SYNOPSIS
colcrt [_] [_2] [file ...]
DESCRIPTION
colcrt provides virtual half-line and reverse-line feed sequences for terminals without such capability, and on which overstriking is destructive. Half-line characters and underlining (changed to dashing _) are placed on new lines in between the normal output lines.
Available options:
| _ | Suppress all underlining. This option is especially useful for previewing all boxed tables from tbl(1). |
| _2 | Causes all half-lines to be printed, effectively double spacing the output. Normally, a minimal space output format is used which will suppress empty lines. The program never suppresses two consecutive empty lines, however. The -2 option is useful for sending output to the line printer when the output contains superscripts and subscripts that would otherwise be invisible. |
EXAMPLES
A typical use of colcrt would be
tbl exum2.n | nroff -ms | colcrt - | more
SEE ALSO
nroff(1), troff(1), col(1), more(1), ul(1)
BUGS
Should fold underlines onto blanks even with the - option so that a true underline character would show.
Can't back up more than 102 lines.
General overstriking is lost; as a special case | overstruck with `' or underline becomes +. Lines are trimmed to 132 characters.
Some provision should be made for processing superscripts and subscripts in documents that are already double-spaced.
HISTORY
The colcrt command appeared in BSD 3.0.
BSD 3, 30 June 1993
colrm—Remove columns from a file
SYNOPSIS
colrm [startcol [endcol]]
DESCRIPTION
colrm removes selected columns from a file. Input is taken from standard input. Output is sent to standard output.
If called with one parameter, the columns of each line will be removed starting with the specified column. If called with two parameters, the columns from the first column to the last column will be removed.
Column numbering starts with column 1.