Difference between revisions of "Linux/C2/File-Attributes/English-timed"
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Sandhya.np14 (Talk | contribs) |
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| − | | Welcome to this spoken tutorial on Linux File Attributes. | + | | Welcome to this spoken tutorial on Linux '''File Attributes'''. |
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| − | |Please create empty directories named as test_chown and directory1 also | + | |Please create empty directories named as 'test_chown' and 'directory1' also. |
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| 00:25 | | 00:25 | ||
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| − | |File attribute is the | + | |File attribute is the characteristic that describes a file such as owner, file type, access permissions etc. |
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| 00:45 | | 00:45 | ||
| − | | c-h own command is used to change the ownership of the file or directory. This is an admin command, root user only can change the owner of a file or directory. | + | | 'c-h own' command is used to change the ownership of the file or directory. This is an admin command, '''root''' user only can change the owner of a file or directory. |
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| − | | We may give following options with chown command. | + | | We may give following options with '''chown''' command. |
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|01:18 | |01:18 | ||
| − | |'''-R''' : To change the permission on files that are in the | + | |'''-R''' : To change the permission on files that are in the sub-directories of the directory that you are currently in. |
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|01:28 | |01:28 | ||
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| − | |'''-f''' : Prevents | + | |'''-f''' : Prevents '''chown''' from displaying error messages. |
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| 01:37 | | 01:37 | ||
| − | | Now we will look at some examples | + | | Now we will look at some examples. |
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| − | | So go to the terminal. We will move to the directory where we have created empty files and folders. For that cd space Desktop slash file attribute and press | + | | So, go to the terminal. We will move to the directory where we have created empty files and folders. For that, '''cd space Desktop slash file attribute''' and press Enter. |
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| 01:56 | | 01:56 | ||
| − | | Now type the command | + | | Now type the command: |
| − | $ ls space -l | + | $ ls space -l space testchown that is t-e-s-t-c-h-o-w-n and press Enter. |
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| 02:11 | | 02:11 | ||
| − | | Here we can see the owner of the file 'testchown' is shahid | + | | Here we can see the owner of the file 'testchown' is shahid. |
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| 02:18 | | 02:18 | ||
| − | | To change the owner of the file, type the command | + | | To change the owner of the file, type the command: |
$ sudo space c-h own space that is a-n-u-s-h-a anusha space testchown that is t-e-s-t-c-h-o-w-n | $ sudo space c-h own space that is a-n-u-s-h-a anusha space testchown that is t-e-s-t-c-h-o-w-n | ||
| − | press Enter | + | press Enter. |
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| 02:36 | | 02:36 | ||
Revision as of 12:35, 10 March 2015
| Time | Narration |
| 00:00 | Welcome to this spoken tutorial on Linux File Attributes. |
| 00:05 | The prerequisite for this tutorial is to create empty files named as example1, example2, example3, example4, example5, and testchown. |
| 00:18 | Please create empty directories named as 'test_chown' and 'directory1' also. |
| 00:25 | A file attribute is metadata that describes or is associated with a computer file. |
| 00:33 | File attribute is the characteristic that describes a file such as owner, file type, access permissions etc. |
| 00:45 | 'c-h own' command is used to change the ownership of the file or directory. This is an admin command, root user only can change the owner of a file or directory. |
| 01:00 | The syntax of chown command is chown space options space ownername space filename or directoryname |
| 01:13 | We may give following options with chown command. |
| 01:18 | -R : To change the permission on files that are in the sub-directories of the directory that you are currently in. |
| 01:28 | -c : Change the permission for each file. |
| 01:33 | -f : Prevents chown from displaying error messages. |
| 01:37 | Now we will look at some examples. |
| 01:40 | So, go to the terminal. We will move to the directory where we have created empty files and folders. For that, cd space Desktop slash file attribute and press Enter. |
| 01:56 | Now type the command:
$ ls space -l space testchown that is t-e-s-t-c-h-o-w-n and press Enter. |
| 02:11 | Here we can see the owner of the file 'testchown' is shahid. |
| 02:18 | To change the owner of the file, type the command:
$ sudo space c-h own space that is a-n-u-s-h-a anusha space testchown that is t-e-s-t-c-h-o-w-n press Enter. |
| 02:36 | Enter the sudo password and press Enter again. Press enter |
| 02:44 | Now type $ ls space -l space t-e-s-t-c-h-o-w-n
and press Enter Here we can see the new owner of the file is anusha. |
| 03:03 | Now we will see how to change owner of the directory |
| 03:07 | Type the command $ ls -l and press Enter
Here we can see the owner of the directory 'test_chown' is shahid |
| 03:21 | To change the owner of the directory, type the command |
| 03:26 | $ sudo space chown space minus capital R space a-n-u-s-h-a anusha spacetest_chown which is directory name
and press Enter |
| 03:44 | Enter the sudo password, if required and press Enter again. |
| 03:49 | I will clear the screen by pressing Clt+L for our convenience. Now type $ ls space -l press Enter
Here we can see the new owner of the directory is anusha. |
| 04:06 | chmod command is used to change the access mode or permissions of one or more files. |
| 04:13 | Syntax of the chmod command is
chmod space [options] space mode space filename space chmod space [options] space filename We may give the following options with chmod command. |
| 04:29 | -c : Print information about files that are changed. |
| 04:34 | -f : Do not notify user of files that chmod cannot change. |
| 04:41 | There are following types of access or permissions |
| 04:44 | r : Read
w : Write x : Execute s : Set user (or group) ID |
| 04:54 | Alternatively, we may specify permissions by a three-digit octal number. |
| 05:00 | The first digit stands for owner permission, the second stands for group permission, and the third stands for other's permission. |
| 05:09 | Permissions are calculated by adding the following octal values:
4 that is Read 2 that is Write 1 that is Execute |
| 05:20 | Now we will look at some examples of chmod Move to terminal and enter the command to add execute-by-user permission to file example1. |
| 05:30 | Before that i will again clear the screen by pressing Clt+l. |
| 05:36 | Now lets type
$ chmod space u+x space example1 press Enter |
| 05:49 | Now type $ ls space -l space example1
press Enter to see the changes |
| 06:01 | here you can see to assign the read/write/execute permission by owner, read/execute permission by group, and execute-only permission by others to file example1 |
| 06:15 | Now type the command $ chmod space 751 space example1
press Enter |
| 06:26 | Now type
$ ls space -l space example1 and press Enter |
| 06:35 | Here we can see that above command has assigned the read/write/execute permission by owner, read/execute permission by group, and execute-only permission by others to file example1. |
| 06:52 | To assign read-only permission to file example1 for everyone type the command $ chmod space =r space example1
and press Enter |
| 07:08 | Now type the command $ ls space -l space example1
press Enter |
| 07:19 | Here we can see that the read only permission has been assigned to file example1 for everyone |
| 07:30 | To change the permission recursively and assign the read and execute access for everyone and also write access for the owner of the directory directory1 type the command |
| 7:44 | $ chmod space minus capital R space 755 space directory1
press Enter |
| 08:00 | Now type
$ ls space -l press Enter to see the changes
|
| 08:09 | To give the user execute permission on file example2 Type the command
$ chmod space u+x space example2 press Enter |
| 08:27 | Now type the command
$ ls space -l space example2 and press Enter |
| 08:40 | Here we can see that execute permission has been assigned to user on example2 |
| 08:50 | To add the write permissions to the group for file example3
type the command $ chmod space g+w space example3 press Enter |
| 09:10 | and now type
$ ls space -l space example3 press Enter |
| 09:23 | Here we can see the write permission has been added to group |
| 09:30 | To remove the write permissions for all type the command
$ chmod space a-w space example3 press Enter |
| 09:45 | Now type
$ ls space -l space example3 press Enter |
| 09:55 | Here we can see the write permission for all has been removed |
| 10:02 | chgrp command is used to change the group of one or more files to newgroup. |
| 10:10 | Newgroup is either a group ID number or a group name located in /etc/group. |
| 10:20 | Only the owner of a file or a privileged user may change the group. |
| 10:26 | The syntax for the chgrp command is
chgrp space [options] space newgroup space files. |
| 10:36 | Lets go to terminal. Now we will look at some examples of chgrp command.
type the command $ ls space -l space example4 press Enter |
| 10:57 | Here we can see the group permission is for user shahid |
| 11:03 | To change the group permission , type the command $ sudo space chgrp space rohit space example4 |
| 11:20 | press Enter
Enter the sudo password if required. |
| 11:27 | Now type the command $ ls space -l space example4
press Enter |
| 11:38 | Here we can see that the group has changed from shahid to rohit. |
| 11:46 | The inode number is a unique integer assigned to the device. |
| 11:51 | Inode stores basic information about a regular file or a directory. |
| 11:57 | All the files are hard links to inodes. |
| 12:00 | Whenever a program refers to a file by name, the system actually uses the filename to search for the corresponding inode. |
| 12:12 | We can use ls space -i command to see the inode number of a file. |
| 12:19 | type the command $ ls space -i space example5
press Enter |
| 12:29 | Number written before the file is the inode number of the file. |
| 12:35 | Inodes are associated with precisely one directory at a time. |
| 12:41 | Hard links are to associate multiple directory entries with a single inode.
ln is the command to make link |
| 12:52 | The syntax of ln command to create the hard link is |
| 12:57 | ln space source space link Where, source is an existing file and link is the file to create. |
| 13:06 | Now we will look at some examples of hard links |
| 13:10 | Let me clear the screen again. Now type the command
$ ln space example1 space exampleln press Enter |
| 13:25 | To display the inode number of both the files, type the command
$ ls space -i space example1 space exampleln press Enter |
| 13:41 | Here we can see that inode number of both the files are same, file exampleln is the hard link for file example1 |
| 13:54 | Soft link symbolic link is a special type of file that contains a reference to another file or directory in the form of an absolute or relative path. |
| 14:07 | The syntax of ln command to create soft links is |
| 14:12 | ln space -s space {target-filename} space {symbolic-filename} |
| 14:19 | Now we will look at some examples of soft link |
| 14:25 | To create the soft link, type the command
$ ln space -s space example1 space examplesoft |
| 14:40 | press Enter |
| 14:43 | Now, to display the inode number and list of both the files, type the command
$ ls space -li space example1 space examplesoft |
| 15:01 | press Enter |
| 15:03 | Here we can see that inode number of both the files are different and examplesoft is a softlink of example1. |
| 15:16 | So in this tutorial we have learnt about the Linux Files Attributes like changing permission, ownership and group of a file. |
| 15:26 | We also learnt about the inode, soft and hard links of a file. |
| 15:31 | This brings me to the end of this tutorial. |
| 15:35 | Spoken Tutorials are a part of the Talk to a Teacher project, supported by the National Mission on Education through ICT. |
| 15:44 | More information on the same is available at the following link. |
| 15:50 | This script has been contributed by ----------------------(name of the translator) and this is -----------------------(name of the recorder) from --------------------------(name of the place)signing off . Thanks for joining. |
