Difference between revisions of "Access type"
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| Read || Examine, print, or copy a file. If you have read access to a directory, you can display the contents of the directory with the DIRECTORY command. For example, | | Read || Examine, print, or copy a file. If you have read access to a directory, you can display the contents of the directory with the DIRECTORY command. For example, | ||
if you have read access to the directory [JONES], you can enter the following command: | if you have read access to the directory [JONES], you can enter the following command: | ||
| − | $ DIRECTORY [JONES] | + | '''$ DIRECTORY [JONES]''' |
This command displays the files contained in the [JONES] directory. With read access, you can access any file listed in the directory, unless the protection on that | This command displays the files contained in the [JONES] directory. With read access, you can access any file listed in the directory, unless the protection on that | ||
| − | + | file denies you access. If the protection applied to the whole directory denies you read access, then you cannot access even those files in the directory that permit | |
access to users in your group. | access to users in your group. | ||
|- | |- | ||
| − | | | + | | Write || Modify or write to a directory. However, you must have both read and write access to a directory to create files in the directory, to rename files in the directory, |
| + | or to perform any file operation that involves changes to the directory file. | ||
|- | |- | ||
| − | | | + | | Execute || Access files by name but not list all the entries in a directory (that is, to use specific or implied wildcards) when applied to directories. |
| + | For example, assume that you have execute access to the [JONES] directory, and you enter the following command: | ||
| + | $ DIRECTORY [JONES] | ||
| + | The system responds with an error message of "insufficient privilege or file protection violation" and does not list the files in the [JONES] directory. However, | ||
| + | if you know that the file DATAFILE.DAT resides in the [JONES] directory, you can enter the following command: | ||
| + | $ TYPE [JONES]DATAFILE.DAT | ||
| + | The system displays the contents of the file. Thus, with execute access, you can perform some, but not all, of the operations that you can with read access. | ||
| + | (Access to individual files is still controlled by their file protection.) | ||
| + | As another example, to display the contents of the EXPENSES.DAT file, you must have read or execute access to each directory in the directory tree, | ||
| + | that is, to the JONES, REPORTS, and JUNE directories: | ||
| + | $ TYPE [JONES.REPORTS.JUNE]EXPENSES.DAT | ||
|- | |- | ||
| Example || Example | | Example || Example | ||
Revision as of 11:45, 31 January 2020
Access Types with Disk File Protection.
| Access type | Gives you the right to... |
|---|---|
| Read | Read, print, or copy a disk file. Read access automatically includes execute access to a specified file or group of files on disk. |
| Write | Write to or change the contents of a file, but not delete it. Write access allows modification of the file characteristics that describe the contents of the file. |
| Execute | Execute a file that contains an executable program image or DCL command procedure. |
| Delete | Delete the file. To delete a file, you must have delete access to the file and write access to the directory that contains the file. |
| Control | Change file characteristics, including the protection code and ACL. Special restrictions apply to changing the owner of a file. |
Access Types for Directory Protection
| Access type | Gives you the right to... |
|---|---|
| Read | Examine, print, or copy a file. If you have read access to a directory, you can display the contents of the directory with the DIRECTORY command. For example,
if you have read access to the directory [JONES], you can enter the following command:
$ DIRECTORY [JONES]
This command displays the files contained in the [JONES] directory. With read access, you can access any file listed in the directory, unless the protection on that
file denies you access. If the protection applied to the whole directory denies you read access, then you cannot access even those files in the directory that permit
access to users in your group.
|
| Write | Modify or write to a directory. However, you must have both read and write access to a directory to create files in the directory, to rename files in the directory,
or to perform any file operation that involves changes to the directory file. |
| Execute | Access files by name but not list all the entries in a directory (that is, to use specific or implied wildcards) when applied to directories.
For example, assume that you have execute access to the [JONES] directory, and you enter the following command:
$ DIRECTORY [JONES]
The system responds with an error message of "insufficient privilege or file protection violation" and does not list the files in the [JONES] directory. However,
if you know that the file DATAFILE.DAT resides in the [JONES] directory, you can enter the following command:
$ TYPE [JONES]DATAFILE.DAT
The system displays the contents of the file. Thus, with execute access, you can perform some, but not all, of the operations that you can with read access.
(Access to individual files is still controlled by their file protection.)
As another example, to display the contents of the EXPENSES.DAT file, you must have read or execute access to each directory in the directory tree,
that is, to the JONES, REPORTS, and JUNE directories:
$ TYPE [JONES.REPORTS.JUNE]EXPENSES.DAT
|
| Example | Example |
| Example | Example |
