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.Id $Id: ci.1,v 5.9 1991/10/07 17:32:46 eggert Exp $
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.TH CI 1 \*(Dt GNU
.SH NAME
ci \- check in RCS revisions
.SH SYNOPSIS
.B ci
.RI [ options ] " file " .\|.\|.
.SH DESCRIPTION
.B ci
stores new revisions into \*r files.
Each pathname matching an \*r suffix
is taken to be an \*r file.
All others
are assumed to be working files containing new revisions.
.B ci
deposits the contents of each working file
into the corresponding \*r file.
If only a working file is given,
.B ci
tries to find the corresponding \*r file in an \*r subdirectory
and then in the working file's directory.
For more details, see
.SM "FILE NAMING"
below.
.PP
For
.B ci
to work, the caller's login must be on the access list,
except if the access list is empty or the caller is the superuser or the
owner of the file.
To append a new revision to an existing branch, the tip revision on
that branch must be locked by the caller.  Otherwise, only a
new branch can be created.  This restriction is not enforced
for the owner of the file if non-strict locking is used
(see
.BR rcs (1)).
A lock held by someone else may be broken with the
.B rcs
command.
.PP
Unless the
.B \-f
option is given,
.B ci
checks whether the revision to be deposited differs from the preceding one.
If not, instead of creating a new revision
.B ci
reverts to the preceding one.
To revert, ordinary
.B ci
removes the working file and any lock;
.B "ci\ \-l"
keeps and
.B "ci\ \-u"
removes any lock, and then they both generate a new working file much as if
.B "co\ \-l"
or
.B "co\ \-u"
had been applied to the preceding revision.
When reverting, any
.B \-n
and
.B \-s
options apply to the preceding revision.
.PP
For each revision deposited,
.B ci
prompts for a log message.
The log message should summarize the change and must be terminated by
end-of-file or by a line containing
.BR \&. "\ by"
itself.
If several files are checked in
.B ci
asks whether to reuse the
previous log message.
If the standard input is not a terminal,
.B ci
suppresses the prompt
and uses the same log message for all files.
See also
.BR \-m .
.PP
If the \*r file does not exist,
.B ci
creates it and
deposits the contents of the working file as the initial revision
(default number:
.BR 1.1 ).
The access list is initialized to empty.
Instead of the log message,
.B ci
requests descriptive text (see
.B \-t
below).
.PP
The number
.I rev
of the deposited revision can be given by any of the options
.BR \-f ,
.BR \-I ,
.BR \-k ,
.BR \-l ,
.BR \-M ,
.BR \-q ,
.BR \-r ,
or
.BR \-u .
.I rev
may be symbolic, numeric, or mixed.
If
.I rev
is
.BR $ ,
.B ci
determines the revision number from keyword values in the working file.
.PP
If
.I rev
is a revision number, it must be higher than the latest
one on the branch to which
.I rev
belongs, or must start a new branch.
.PP
If
.I rev
is a branch rather than a revision number,
the new revision is appended to that branch.  The level number is obtained
by incrementing the tip revision number of that branch.
If
.I rev
indicates a non-existing branch,
that branch is created with the initial revision numbered
.IB rev .1\f1.\fP
.br
.ne 8
.PP
If
.I rev
is omitted,
.B ci
tries to derive the new revision number from
the caller's last lock.  If the caller has locked the tip revision of a branch,
the new revision is appended to that branch.
The new revision number is obtained
by incrementing the tip revision number.
If the caller locked a non-tip revision, a new branch is started at
that revision by incrementing the highest branch number at that revision.
The default initial branch and level numbers are
.BR 1 .
.PP
If
.I rev
is omitted and the caller has no lock, but owns
the file and locking
is not set to
.IR strict ,
then the revision is appended to the
default branch (normally the trunk; see the
.B \-b
option of
.BR rcs (1)).
.PP
Exception: On the trunk, revisions can be appended to the end, but
not inserted.
.SH OPTIONS
.TP
.BR \-r [\f2rev\fP]
checks in a revision, releases the corresponding lock, and
removes the working file.  This is the default.
.RS
.PP
The
.B \-r
option has an unusual meaning in
.BR ci .
In other \*r commands,
.B \-r
merely specifies a revision number,
but in
.B ci
it also releases a lock and removes the working file.
See
.B \-u
for a tricky example.
.RE
.TP
.BR \-l [\f2rev\fP]
works like
.BR \-r ,
except it performs an additional
.B "co\ \-l"
for the
deposited revision.  Thus, the deposited revision is immediately
checked out again and locked.
This is useful for saving a revision although one wants to continue
editing it after the checkin.
.TP
.BR \-u [\f2rev\fP]
works like
.BR \-l ,
except that the deposited revision is not locked.
This lets one read the working file
immediately after checkin.
.RS
.PP
The
.BR \-l ,
.BR \-r ,
and
.B \-u
options are mutually exclusive and silently override each other.
For example,
.B "ci\ \-u\ \-r"
is equivalent to
.B "ci\ \-r"
because
.B \-r
overrides
.BR \-u .
.RE
.TP
.BR \-f [\f2rev\fP]
forces a deposit; the new revision is deposited even it is not different
from the preceding one.
.TP
.BR \-k [\f2rev\fP]
searches the working file for keyword values to determine its revision number,
creation date, state, and author (see
.BR co (1)),
and assigns these
values to the deposited revision, rather than computing them locally.
It also generates a default login message noting the login of the caller
and the actual checkin date.
This option is useful for software distribution.  A revision that is sent to
several sites should be checked in with the
.B \-k
option at these sites to
preserve the original number, date, author, and state.
The extracted keyword values and the default log message may be overridden
with the options
.BR \-d ,
.BR \-m ,
.BR \-s ,
.BR \-w ,
and any option that carries a revision number.
.TP
.BR \-q [\f2rev\fP]
quiet mode; diagnostic output is not printed.
A revision that is not different from the preceding one is not deposited,
unless
.B \-f
is given.
.TP
.BR \-I [\f2rev\fP]
interactive mode;
the user is prompted and questioned
even if the standard input is not a terminal.
.TP
.BR \-d "[\f2date\fP]"
uses
.I date
for the checkin date and time.
The
.I date
is specified in free format as explained in
.BR co (1).
This is useful for lying about the checkin date, and for
.B \-k
if no date is available.
If
.I date
is empty, the working file's time of last modification is used.
.TP
.BR \-M [\f2rev\fP]
Set the modification time on any new working file
to be the date of the retrieved revision.
For example,
.BI "ci\ \-d\ \-M\ \-u" "\ f"
does not alter
.IR f 's
modification time, even if
.IR f 's
contents change due to keyword substitution.
Use this option with care; it can confuse
.BR make (1).
.TP
.BI \-m "msg"
uses the string
.I msg
as the log message for all revisions checked in.
.TP
.BI \-n "name"
assigns the symbolic name
.I name
to the number of the checked-in revision.
.B ci
prints an error message if
.I name
is already assigned to another
number.
.TP
.BI \-N "name"
same as
.BR \-n ,
except that it overrides a previous assignment of
.IR name .
.TP
.BI \-s "state"
sets the state of the checked-in revision to the identifier
.IR state .
The default state is
.BR Exp .
.TP
.BI \-t file
writes descriptive text from the contents of the named
.I file
into the \*r file,
deleting the existing text.
The
.I file
may not begin with
.BR \- .
.TP
.BI \-t\- string
Write descriptive text from the
.I string
into the \*r file, deleting the existing text.
.RS
.PP
The
.B \-t
option, in both its forms, has effect only during an initial checkin;
it is silently ignored otherwise.
.PP
During the initial checkin, if
.B \-t
is not given,
.B ci
obtains the text from standard input,
terminated by end-of-file or by a line containing
.BR \&. "\ by"
itself.
The user is prompted for the text if interaction is possible; see
.BR \-I .
.PP
For backward compatibility with older versions of \*r, a bare
.B \-t
option is ignored.
.RE
.TP
.BI \-w "login"
uses
.I login
for the author field of the deposited revision.
Useful for lying about the author, and for
.B \-k
if no author is available.
.TP
.BI \-V n
Emulate \*r version
.IR n .
See
.BR co (1)
for details.
.TP
.BI \-x "suffixes"
specifies the suffixes for \*r files.
A nonempty suffix matches any pathname ending in the suffix.
An empty suffix matches any pathname of the form
.BI RCS/ file
or
.IB path /RCS/ file.
The
.B \-x
option can specify a list of suffixes
separated by
.BR / .
For example,
.B \-x,v/
specifies two suffixes:
.B ,v
and the empty suffix.
If two or more suffixes are specified,
they are tried in order when looking for an \*r file;
the first one that works is used for that file.
If no \*r file is found but an \*r file can be created,
the suffixes are tried in order
to determine the new \*r file's name.
The default for
.IR suffixes
is installation-dependent; normally it is
.B ,v/
for hosts like Unix that permit commas in file names,
and is empty (i.e. just the empty suffix) for other hosts.
.SH "FILE NAMING"
Pairs of \*r files and working files may be specified in three ways
(see also the
example section).
.PP
1) Both the \*r file and the working file are given.  The \*r pathname is of
the form
.IB path1 / workfileX
and the working pathname is of the form
.IB path2 / workfile
where
.IB path1 /
and
.IB path2 /
are (possibly different or empty) paths,
.I workfile
is a filename, and
.I X
is an \*r suffix.
If
.I X
is empty,
.IB path1 /
must be
.B RCS/
or must end in
.BR /RCS/ .
.PP
2) Only the \*r file is given.  Then the working file is created in the current
directory and its name is derived from the name of the \*r file
by removing
.IB path1 /
and the suffix
.IR X .
.PP
3) Only the working file is given.
Then
.B ci
considers each \*r suffix
.I X
in turn, looking for an \*r file of the form
.IB path2 /RCS/ workfileX
or (if the former is not found and
.I X
is nonempty)
.IB path2 / workfileX.
.PP
If the \*r file is specified without a path in 1) and 2),
.B ci
looks for the \*r file first in the directory
.B ./RCS
and then in the current
directory.
.PP
.B ci
reports an error if an attempt to open an \*r file fails for an unusual reason,
even if the \*r file's pathname is just one of several possibilities.
For example, to suppress use of \*r commands in a directory
.IR d ,
create a regular file named
.IB d /RCS
so that casual attempts to use \*r commands in
.I d
fail because
.IB d /RCS
is not a directory.
.SH EXAMPLES
Suppose
.B ,v
is an \*r suffix and the current directory contains a subdirectory
.B RCS
with an \*r file
.BR io.c,v .
Then each of the following commands check in a copy of
.B io.c
into
.B RCS/io.c,v
as the latest revision, removing
.BR io.c .
.LP
.RS
.nf
.ft 3
ci  io.c;    ci  RCS/io.c,v;   ci  io.c,v;
ci  io.c  RCS/io.c,v;    ci  io.c  io.c,v;
ci  RCS/io.c,v  io.c;    ci  io.c,v  io.c;
.ft
.fi
.RE
.PP
Suppose instead that the empty suffix
is an \*r suffix and the current directory contains a subdirectory
.B RCS
with an \*r file
.BR io.c .
The each of the following commands checks in a new revision.
.LP
.RS
.nf
.ft 3
ci  io.c;    ci  RCS/io.c;
ci  io.c  RCS/io.c;
ci  RCS/io.c  io.c;
.ft
.fi
.RE
.SH "FILE MODES"
An \*r file created by
.B ci
inherits the read and execute permissions
from the working file.  If the \*r file exists already,
.B ci
preserves its read and execute permissions.
.B ci
always turns off all write permissions of \*r files.
.SH FILES
Several temporary files may be created in the directory containing
the working file, and also in the temporary directory (see
.B \s-1TMPDIR\s0
under
.BR \s-1ENVIRONMENT\s0 ).
A semaphore file or files are created in the directory containing the \*r file.
With a nonempty suffix, the semaphore names begin with
the first character of the suffix; therefore, do not specify an suffix
whose first character could be that of a working filename.
With an empty suffix, the semaphore names end with
.B _
so working filenames should not end in
.BR _ .
.PP
.B ci
never changes an \*r or working file.
Normally,
.B ci
unlinks the file and creates a new one;
but instead of breaking a chain of one or more symbolic links to an \*r file,
it unlinks the destination file instead.
Therefore,
.B ci
breaks any hard or symbolic links to any working file it changes;
and hard links to \*r files are ineffective,
but symbolic links to \*r files are preserved.
.PP
The effective user must be able to
search and write the directory containing the \*r file.
Normally, the real user must be able to
read the \*r and working files
and to search and write the directory containing the working file;
however, some older hosts
cannot easily switch between real and effective users,
so on these hosts the effective user is used for all accesses.
The effective user is the same as the real user
unless your copies of
.B ci
and
.B co
have setuid privileges.
As described in the next section,
these privileges yield extra security if
the effective user owns all \*r files and directories,
and if only the effective user can write \*r directories.
.PP
Users can control access to \*r files by setting the permissions
of the directory containing the files; only users with write access
to the directory can use \*r commands to change its \*r files.
For example, in hosts that allow a user to belong to several groups,
one can make a group's \*r directories writable to that group only.
This approach suffices for informal projects,
but it means that any group member can arbitrarily change the group's \*r files,
and can even remove them entirely.
Hence more formal projects sometimes distinguish between an \*r administrator,
who can change the \*r files at will, and other project members,
who can check in new revisions but cannot otherwise change the \*r files.
.SH "SETUID USE"
To prevent anybody but their \*r administrator from deleting revisions,
a set of users can employ setuid privileges as follows.
.nr n \w'\(bu '+1n-1/1n
.IP \(bu \nn
Check that the host supports \*r setuid use.
Consult a trustworthy expert if there are any doubts.
It is best if the
.B seteuid()
system call works as described in Posix 1003.1a Draft 5,
because \*r can switch back and forth easily
between real and effective users, even if the real user is
.BR root .
If not, the second best is if the
.B setuid()
system call supports saved setuid
(the {\s-1_POSIX_SAVED_IDS\s0} behavior of Posix 1003.1-1990);
this fails only if the real user is
.BR root .
If \*r detects any failure in setuid, it quits immediately.
.IP \(bu \nn
Choose a user
.I A
to serve as \*r administrator for the set of users.
Only
.I A
will be able to invoke the
.B rcs
command on the users' \*r files.
.I A
should not be
.B root
or any other user with special powers.
Mutually suspicious sets of users should use different administrators.
.IP \(bu \nn
Choose a path name
.I B
that will be a directory of files to be executed by the users.
.IP \(bu \nn
Have
.I A
set up
.I B
to contain copies of
.B ci
and
.B co
that are setuid to
.I A
by copying the commands from their standard installation directory
.I D
as follows:
.LP
.RS
.nf
.ne 3
\f3mkdir\fP  \f2B\fP
\f3cp\fP  \f2D\fP\^\f3/c[io]\fP  \f2B\fP
\f3chmod  go\-w,u+s\fP  \f2B\fP\f3/c[io]\fP
.fi
.RE
.IP \(bu \nn
Have each user prepend
.I B
to their path as follows:
.LP
.RS
.nf
.ne 2
\f3PATH=\fP\f2B\fP\f3:$PATH;  export  PATH\fP  # ordinary shell
\f3set  path=(\fP\f2B\fP  \f3$path)\fP  # C shell
.fi
.RE
.IP \(bu \nn
Have
.I A
create each \*r directory
.I R
with write access only to
.I A
as follows:
.LP
.RS
.nf
.ne 2
\f3mkdir\fP  \f2R\fP
\f3chmod  go\-w\fP  \f2R\fP
.fi
.RE
.IP \(bu \nn
If you want to let only certain users read the \*r files,
put the users into a group
.IR G ,
and have
.I A
further protect the \*r directory as follows:
.LP
.RS
.nf
.ne 2
\f3chgrp\fP  \f2G  R\fP
\f3chmod  g\-w,o\-rwx\fP  \f2R\fP
.fi
.RE
.IP \(bu \nn
Have
.I A
copy old \*r files (if any) into
.IR R ,
to ensure that
.I A
owns them.
.IP \(bu \nn
An \*r file's access list limits who can check in and lock revisions.
The default access list is empty,
which grants checkin access to anyone who can read the \*r file.
If you want limit checkin access,
have
.I A
invoke
.B "rcs\ \-a"
on the file; see
.BR rcs (1).
In particular,
.BI "rcs\ \-e\ \-a" A
limits access to just
.IR A .
.IP \(bu \nn
Have
.I A
initialize any new \*r files with
.B "rcs\ \-i"
before initial checkin, adding the
.B \-a
option if you want to limit checkin access.
.IP \(bu \nn
Give setuid privileges only to
.BR ci ,
.BR co ,
and
.BR rcsclean ;
do not give them to
.B rcs
or to any other command.
.IP \(bu \nn
Do not use other setuid commands to invoke \*r commands;
setuid is trickier than you think!
.SH ENVIRONMENT
.TP
.B \s-1RCSINIT\s0
options prepended to the argument list, separated by spaces.
A backslash escapes spaces within an option.
The
.B \s-1RCSINIT\s0
options are prepended to the argument lists of most \*r commands.
Useful
.B \s-1RCSINIT\s0
options include
.BR \-q ,
.BR \-V ,
and
.BR \-x .
.TP
.B \s-1TMPDIR\s0
Name of the temporary directory.
If not set, the environment variables
.B \s-1TMP\s0
and
.B \s-1TEMP\s0
are inspected instead and the first value found is taken;
if none of them are set,
a host-dependent default is used, typically
.BR /tmp .
.SH DIAGNOSTICS
For each revision,
.B ci
prints the \*r file, the working file, and the number
of both the deposited and the preceding revision.
The exit status is zero if and only if all operations were successful.
.SH IDENTIFICATION
Author: Walter F. Tichy.
.br
Revision Number: \*(Rv; Release Date: \*(Dt.
.br
Copyright \(co 1982, 1988, 1989 by Walter F. Tichy.
.br
Copyright \(co 1990, 1991 by Paul Eggert.
.SH "SEE ALSO"
co(1), ident(1), make(1), rcs(1), rcsclean(1), rcsdiff(1),
rcsintro(1), rcsmerge(1), rlog(1), rcsfile(5)
.br
Walter F. Tichy,
\*r\*-A System for Version Control,
.I "Software\*-Practice & Experience"
.BR 15 ,
7 (July 1985), 637-654.
.br