NAMEco - check out RCS revisions
SYNOPSISco [options] file ...
DESCRIPTIONco retrieves a revision from each
Filenames matching an
Revisions of an
A revision is selected by options for revision or branch number, checkin date/time, author, or state. When the selection options are applied in combination, co retrieves the latest revision that satisfies all of them. If none of the selection options is specified, co retrieves the latest revision on the default branch (normally the trunk, see the -b option of rcs(1)). A revision or branch number can be attached to any of the options -f, -I, -l, -M, -p, -q, -r, or -u. The options -d (date), -s (state), and -w (author) retrieve from a single branch, the selected branch, which is either specified by one of -f, ..., -u, or the default branch.
A co command applied to an
- retrieves the latest revision whose number is less than or equal to rev. If rev indicates a branch rather than a revision, the latest revision on that branch is retrieved. If rev is omitted, the latest revision on the default branch (see the -b option of rcs(1)) is retrieved. If rev is $, co determines the revision number from keyword values in the working file. Otherwise, a revision is composed of one or more numeric or symbolic fields separated by periods. If rev begins with a period, then the default branch (normally the trunk) is prepended to it. If rev is a branch number followed by a period, then the latest revision on that branch is used. The numeric equivalent of a symbolic field is specified with the -n option of the commands ci(1) and rcs(1).
- same as -r, except that it also locks the retrieved revision for the caller.
- same as -r, except that it unlocks the retrieved revision if it was locked by the caller. If rev is omitted, -u retrieves the revision locked by the caller, if there is one; otherwise, it retrieves the latest revision on the default branch.
forces the overwriting of the working file;
useful in connection with
- Generate keyword strings using the default form, e.g. $Revision: 5.9.4 $ for the Revision keyword. A locker's name is inserted in the value of the Header, Id, and Locker keyword strings only as a file is being locked, i.e. by ci -l and co -l. This is the default.
- Like -kkv, except that a locker's name is always inserted if the given revision is currently locked.
Generate only keyword names in keyword strings; omit their values.
KEYWORD SUBSTITUTIONbelow. For example, for the Revision keyword, generate the string $Revision$ instead of $Revision: 5.9.4 $. This option is useful to ignore differences due to keyword substitution when comparing different revisions of a file. Log messages are inserted after $Log$ keywords even if -kk is specified, since this tends to be more useful when merging changes.
- Generate the old keyword string, present in the working file just before it was checked in. For example, for the Revision keyword, generate the string $Revision: 1.1 $ instead of $Revision: 5.9.4 $ if that is how the string appeared when the file was checked in. This can be useful for file formats that cannot tolerate any changes to substrings that happen to take the form of keyword strings.
Generate a binary image of the old keyword string.
This acts like
except it performs all working file input and output in binary mode.
This makes little difference on Posix and Unix hosts,
but on DOS-like hosts one should use
rcs -i -kb
to initialize an RCSfile intended to be used for binary files. Also, on all hosts, rcsmerge(1) normally refuses to merge files when -kb is in effect.
- Generate only keyword values for keyword strings. For example, for the Revision keyword, generate the string 5.9.4 instead of $Revision: 5.9.4 $. This can help generate files in programming languages where it is hard to strip keyword delimiters like $Revision: $ from a string. However, further keyword substitution cannot be performed once the keyword names are removed, so this option should be used with care. Because of this danger of losing keywords, this option cannot be combined with -l, and the owner write permission of the working file is turned off; to edit the file later, check it out again without -kv.
- prints the retrieved revision on the standard output rather than storing it in the working file. This option is useful when co is part of a pipe.
- quiet mode; diagnostics are not printed.
- interactive mode; the user is prompted and questioned even if the standard input is not a terminal.
retrieves the latest revision on the selected branch whose checkin date/time is
less than or equal to
The date and time can be given in free format.
The time zone
stands for local time;
other common time zone names are understood.
For example, the following
if local time is January 11, 1990, 8pm Pacific Standard Time,
eight hours west of Coordinated Universal Time (UTC):
8:00 pm lt 4:00 AM, Jan. 12, 1990 default isUTC1990-01-12 04:00:00+00ISO8601 (UTC) 1990-01-11 20:00:00-08ISO8601 (local time) 1990/01/12 04:00:00 traditionalRCSformat Thu Jan 11 20:00:00 1990 LT output of ctime(3) + LT Thu Jan 11 20:00:00 PST 1990 output of date(1) Fri Jan 12 04:00:00 GMT 1990 Thu, 11 Jan 1990 20:00:00 -0800 Internet RFC 822 12-January-1990, 04:00 WET
Most fields in the date and time can be defaulted. The default time zone is normallyUTC, but this can be overridden by the -z option. The other defaults are determined in the order year, month, day, hour, minute, and second (most to least significant). At least one of these fields must be provided. For omitted fields that are of higher significance than the highest provided field, the time zone's current values are assumed. For all other omitted fields, the lowest possible values are assumed. For example, without -z, the date 20, 10:30 defaults to 10:30:00UTCof the 20th of theUTCtime zone's current month and year. The date/time must be quoted if it contains spaces.
- Set the modification time on the new working file to be the date of the retrieved revision. Use this option with care; it can confuse make(1).
- retrieves the latest revision on the selected branch whose state is set to state.
- Enable self-same mode. In this mode, the owner of a lock is unimportant, just that it exists. Effectively, this means the user cannot check out the same revision twice.
Preserve the modification time on the RCSfile even if theRCSfile changes because a lock is added or removed. This option can suppress extensive recompilation caused by a make(1) dependency of some other copy of the working file on theRCSfile. Use this option with care; it can suppress recompilation even when it is needed, i.e. when the change of lock would mean a change to keyword strings in the other working file.
- retrieves the latest revision on the selected branch which was checked in by the user with login name login. If the argument login is omitted, the caller's login is assumed.
generates a new revision which is the join of the revisions on
This option is largely obsoleted by
but is retained for backwards compatibility.
The joinlist is a comma-separated list of pairs of the form rev2:rev3, where rev2 and rev3 are (symbolic or numeric) revision numbers. For the initial such pair, rev1 denotes the revision selected by the above options -f, ..., -w. For all other pairs, rev1 denotes the revision generated by the previous pair. (Thus, the output of one join becomes the input to the next.)
For each pair, co joins revisions rev1 and rev3 with respect to rev2. This means that all changes that transform rev2 into rev1 are applied to a copy of rev3. This is particularly useful if rev1 and rev3 are the ends of two branches that have rev2 as a common ancestor. If rev1<rev2<rev3 on the same branch, joining generates a new revision which is like rev3, but with all changes that lead from rev1 to rev2 undone. If changes from rev2 to rev1 overlap with changes from rev2 to rev3, co reports overlaps as described in merge(1).
For the initial pair, rev2 can be omitted. The default is the common ancestor. If any of the arguments indicate branches, the latest revisions on those branches are assumed. The options -l and -u lock or unlock rev1.
Print RCS's version number.
Emulate RCSversion n, where n can be 3, 4, or 5. This can be useful when interchangingRCSfiles with others who are running older versions ofRCS. To see which version ofRCSyour correspondents are running, have them invoke rcs -V; this works with newer versions ofRCS. If it doesn't work, have them invoke rlog on anRCSfile; if none of the first few lines of output contain the string branch: it is version 3; if the dates' years have just two digits, it is version 4; otherwise, it is version 5. AnRCSfile generated while emulating version 3 loses its default branch. AnRCSrevision generated while emulating version 4 or earlier has a time stamp that is off by up to 13 hours. A revision extracted while emulating version 4 or earlier contains abbreviated dates of the form yy/mm/dd and can also contain different white space and line prefixes in the substitution for $Log$.
to characterize RCSfiles. See ci(1) for details.
specifies the date output format in keyword substitution,
and specifies the default time zone for
should be empty, a numeric UTCoffset, or the special string LT for local time. The default is an empty zone, which uses the traditionalRCSformat ofUTCwithout any time zone indication and with slashes separating the parts of the date; otherwise, times are output inISO8601 format with time zone indication. For example, if local time is January 11, 1990, 8pm Pacific Standard Time, eight hours west ofUTC, 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 inRCSfiles, which are alwaysUTC.
KEYWORD SUBSTITUTIONStrings 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 listed below. 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:
- The login name of the user who checked in the revision.
The date and time the revision was checked in.
a numeric time zone offset is appended; otherwise, the date is UTC.
A standard header containing the full RCSfile name, 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 isUTC.
except that the RCSfile name is without the directory components.
- The login name of the user who locked the revision (empty if not locked).
The log message supplied during checkin, preceded by a header
containing the RCSfile name, the revision number, the author, and the date and time. With -zzone a numeric time zone offset is appended; otherwise, the date isUTC. 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 $'',RCSprefixes 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 `` * rq 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 ofRCS, if the log prefix is /* or (* surrounded by optional white space, inserted log lines contain a space instead of / or (; however, this usage is obsolescent and should not be relied on.
- The symbolic name used to check out the revision, if any. For example, co -rJoe generates $Name: Joe $. Plain co generates just $Name: $.
The RCSfile name without directory components.
- The revision number assigned to the revision.
The full RCSfile name.
- 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.
char escape sequence tab \t newline \n space \040 $ \044 \ \\
FILE MODESThe working file inherits the read and execute permissions from the
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.
FILESco 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.
Options prepended to the argument list, separated by spaces.
A backslash escapes spaces within an option.
RCSINIToptions are prepended to the argument lists of mostRCScommands. UsefulRCSINIToptions include -q, -V, -x, and -z.
Normally, for speed, commands either memory map or copy into memory
the RCSfile if its size is less than the memory-limit, currently defaulting to ``unlimited''. Otherwise (or if the initially-tried speedy ways fail), the commands fall back to using standard i/o routines. You can adjust the memory limit by settingRCS_MEM_LIMITto a numeric value lim (measured in kilobytes). An empty value is silently ignored. As a side effect, specifyingRCS_MEM_LIMITinhibits fall-back to slower routines.
Name of the temporary directory.
If not set, the environment variables
TMPandTEMPare inspected instead and the first value found is taken; if none of them are set, a host-dependent default is used, typically /tmp.
IDENTIFICATIONAuthor: Walter F. Tichy.
Manual Page Revision: 5.9.4; Release Date: 2015-06-21.
Copyright © 2010-2015 Thien-Thi Nguyen.
Copyright © 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
Copyright © 1982, 1988, 1989 Walter F. Tichy.
SEE ALSOci(1), ctime(3), date(1), ident(1), make(1), rcs(1), rcsclean(1), rcsdiff(1), rcsmerge(1), rlog(1), rcsfile(5).
Walter F. Tichy,
The full documentation for
- info rcs
should give you access to the complete manual. Additionally, the
has news and links to the latest release, development site, etc.
LIMITSLinks to the
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
into the keyword.