admin Command (SCCS)

Purpose

Creates and controls Source Code Control System (SCCS) files.

Syntax

To Create New SCCS Files

admin { -n -i[FileName ] } [ -a { User | GroupID } ] ... [ -f HeaderFlag[Value ] ... ] [ -r SID ] [ -t FileName ] [ -m ModificationRequestList ] [ -y[Comment ] ] File ...

Note: Do not put a space between a flag and an optional (bracketed) variable.

To Modify Existing SCCS Files

admin [ -a { User | GroupID } ] ... [ -e { User | GroupID } ] ... [ { -d HeaderFlag | -f HeaderFlag[Value ] ... } ] [ -m ModificationRequestList ] [ -t[FileName ] ] [ -y[Comment ] ] File ...

Note: Do not put a space between a flag and an optional (bracketed) variable.

To Check Damaged SCCS Files

admin -h File ...

To Correct Damaged SCCS Files

admin -z File ...

Description

The admin command creates new Source Code Control System (SCCS) files or changes specified parameters in existing SCCS files.

The admin command can change the parameters controlling how the get command builds the files that you can edit. The parameters can also set conditions about who can access the file and which releases of the files may be edited.

If the file specified by the File parameter exists, the admin command modifies the file as specified by the flags. If the file does not exist and you supply the -i or -n flag, the admin command creates a new file and provides default values for unspecified flags.

If you specify a directory name for the File parameter, the admin command performs the requested actions on all SCCS files in that directory. All SCCS files contain the s. prefix before the file name. If you use a - (minus sign) for the File parameter, the admin command reads standard input and interprets each line as the name of an SCCS file. An end-of-file character ends input.

You must have write permission in the directory to create a file. All SCCS file names must have the form s.Name. New SCCS files are created with read-only permission. The admin command writes to a temporary x-file, which it calls x.Name. If it already exists, the x-file has the same permissions as the original SCCS file. The x-file is read-only if the admin command must create a new file. After successful completion of the admin command, the x-file is moved to the name of the SCCS file. This ensures that changes are made to the SCCS file only if the admin command does not detect any errors while running.

Directories containing SCCS files should be created with permission code 755 (read, write, and execute permissions for owner, read and execute permissions for group members and others). The SCCS files themselves should be created as read-only files (444). With these permissions, only the owner can use non-SCCS commands to modify SCCS files. If a group can access and modify the SCCS files, the directories should include group write permission.

The admin command also uses a temporary lock file (called z.Name), to prevent simultaneous updates to the SCCS file by different users.

You can enter flags and input file names in any order. All flags apply to all the files. Do not put a space between a flag and an optional variable (variable enclosed in bracket). Header flags can be set with the -f flag and unset with the -d flag. Header flags control the format of the g-file created with the get command.

Flags

date and time created YY/MM/DD HH:MM:SS by Login

Header Flags

The following list contains the header flags that can be set with the -f flag and unset with the -d flag. Header flags control the format of the g-file created with the get command.

There are no SCCS identification keywords in the file. (cm7) 

<List> : : = <Range> | <List> , <Range>
<Range> : : = SID | a

Locating Damaged SCCS Files

Although SCCS provides some error protection, you may need to recover a file that was accidentally damaged. This damage may result from a system malfunction, operator error, or changing an SCCS file without using SCCS commands.

SCCS commands use the checksum to determine whether a file was changed since it was last used. The only SCCS command that processes a damaged file is the admin command when used with the -h or -z flags. The -h flag tells the admin command to compare the checksum stored in the SCCS file header against the computed checksum. The -z flag tells the command to re-compute the checksum and store it in the file header.

Exit Status

This command returns the following exit values:

Examples

These examples use an imaginary text file called test.c and an editor such as ed to edit files.

1. First, create an ordinary SCCS file. To create an empty SCCS file named s.test.c, enter:

   $ admin -n s.test.c

   Using the admin command with the -n flag creates an empty SCCS file.
2. To convert an existing text file into an SCCS file, enter:

   $ admin -itest.c s.test.c
   There are no SCCS identification keywords in the file (cm7)
   $ li
   s.test.c test.c

   If you use the -i flag, the admin command creates delta 1.1 from the specified file. Once delta 1.1 is created, rename the original text file so it does not interfere with SCCS commands:

   $ mv test.c back.c

   The message There are no SCCS identification keywords in the file (cm7) does not indicate an error. SCCS writes this message when there are no identification keywords in the file. Identification keywords are variables that can be placed in an SCCS file. The values of these variables provide information such as date, time, SID, or file name. See the get command for an explanation of identification keywords. If no identification keywords exist, SCCS writes the message. However, if the i header flag is set in the s. file, this message causes an error condition. This flag is set by the user.

   Give the SCCS file any name, beginning with s.. In the preceding example, the original file and the SCCS file have the same name, but that is not necessary.

   Because you did not specify a release number, the admin command gave the SCCS file an SID of 1.1. SCCS does not use the number 0 to identify deltas. Therefore, a file cannot have an SID of 1.0 or 2.1.1.0, for example. All new releases start with level 1.

3. To start the test.c file with a release number of 3.1, use the -r flag with the admin command, as shown below, and enter:

   $ admin -itest.c -r3 s.test.c

   To restrict permission to change SCCS files to a specific set of user IDs, list user IDs or group ID numbers in the user list of the SCCS file by using the -a flag of the admin command. This flag may appear multiple times on the command line. These IDs then appear in the SCCS file header. Without the -a flag to restrict access, all user IDs can change the SCCS files.
4. To restrict edit permission to the user ID dan, enter:

   $ admin -adan s.test.c

5. Check SCCS files on a regular basis for possible damage. The easiest way to do this is to run the admin command with the -h flag on all SCCS files or SCCS directories, as follows:

   $ admin -h s.file1 s.file2 ...
   $ admin -h directory1 directory2 ...

   If the admin command finds a file where the computed checksum is not equal to the checksum listed in the SCCS file header, it displays this message:

   ERROR [s. filename]:
   1255-057 The file is damaged. (co6)

   If a file was damaged, try to edit the file again or read a backup copy. After fixing the file, run the admin command with the -z flag and the repaired file name:

   $ admin -z s.file1

   This operation replaces the old checksum in the SCCS file header with a new checksum based on the current file contents. Other SCCS commands can now process the file.

Files

Related Information

The delta command, ed command, get command, prs command, sccshelp command, what command.

The sccsfile file format.

List of SCCS Commands in AIX General Programming Concepts: Writing and Debugging Programs.

Source Code Control System (SCCS) Overview in AIX General Programming Concepts: Writing and Debugging Programs.