Intel XENIX 286 Programmers Guide (86) - Tenox.tc

XENIX Programming SCCS: Source Code Control System
sees Working Files
SCCS uses several different kinds of files to complete its tasks. In general, these files
contain information about the commands in progress or contain actual text. For
convenience, SCCS names these files by placing a prefix before the name of the original
file from which all versions are made. The following is a list of the working files:
s-file
x-file
g-file
p-file
z-file
1-file
d-file
q-file
Contains all versions of the given text file. The versions are stored as
deltas, that is, lists of changes to be applied to the original file to create the
given version. The name of an s-file is formed by placing the prefix s. at the
beginning of the original file name.
A temporary copy of the s-file. It is created by SCCS commands that change
the s-file and is used instead of the s-file to carry out the changes. When all
changes are complete, sees removes the original · file and gives the x-file
the name of the original s-file. The name of the x-file is formed by placing
the prefix x. at the beginning of the original file name.
An ordinary text file created by applying the deltas in a given s-file to the
original file. The g-file represents a copy of the given version of the original
file and as such receives the same file name as the original. When created, a
g-file is placed in the current working directory of the user who requested
the file.
A special file containing information about the versions of an s-file currently
being edited. The p-file is created when a g-file is retrieved from the s-file.
The file remains until all currently retrieved files have been saved in the sfile.
The p-file contains one or more entries describing the SID of the
retrieved g-file, the proposed SID of the new, edited g-file, and the login
name of the user who retrieved the g-file. The p-file name is formed by
placing the prefix p. at the beginning of the original file name.
A lock file used by sees commands to prevent two users from updating a
single SCCS file at the same time. Before a command modifies an SCCS
file, it creates a z-file and copies its own process ID to it. Any other
command that attempts to access the file while the z-file is present displays
an error message and stops. When the original command has finished its
tasks, it deletes the z-file before stopping. The z-file name is formed by
placing the prefix z. at the beginning of the original file name.
A special file containing a list of the deltas required to create a given
version of a file. The 1-file name is formed by placing the prefix 1. at the
beginning of the original file name.
A temporary copy of the g-file used to generate a new delta.
A tem porary file used by the delta command when updating the
corresponding p-file. The q-file is not directly accessible.
In general, a user never directly accesses x-files, z-files, d-files, or q-files. If a system
crash or sim ilar situation abnormally terminates a command, the user may wish to
delete these files before using the sees commands.
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