Visual QuickStart Guide [Electronic resources] : Mac OS X 10.4 Tiger

Maria Langer

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Removing Files & Directories with rm & rmdir

Unix includes two commands that you can use to delete files and directories: rm (remove) and rmdir (remove directory).

Warning!

    rm may be the most dangerous command in Unix. Because Unix doesn't have a Trash that lets you recover mistakenly deleted files, when you delete a file, it's gone forever.

Tips

    There are two options that you may want to use with the rm command:

      -i tells the rm command to ask permission before deleting each file (Figure 24 ). You must press and then at each prompt to delete the file. This is especially useful when using the rm command with wildcard characters, since it can help prevent files from being accidentally deleted.

      Figure 24. The

      rm command in action, with and without the

      -i option.

      -R, which stands for

      recursively , tells the rm command to delete everything within a directory, including its sub-directories and their contents. The -R option can be very dangerous; you may want to use it in conjunction with the -i option to confirm each deletion.

    The rm command's

    file operand can be a file or a directory name. If you are deleting a non-empty directory, you must use the -R (recursive) option.

    You can learn more about the rm and rmdir commands and their options on their man pages. Type man rm or man rmdir and press to view each command's man pages.

To remove a file

Type rm

file ... and press . For example, rm file1 removes the file named

file1 from the current directory (Figure 24 ).

To remove files using a wildcard character

Type rm followed by the wildcard search string and press . For example, rm *.bak removes all files ending with

.bak from the current directory.

To remove all files in a directory

Type rm * and press (Figure 25 ).

Figure 25. Two more examples of the

rm command. In the first, the

rm * command string deletes all files in the directory, but not the subdirectory named dir30. In the second, the

-Ri options delete all contents with confirmation; the only item still in the directory is the subdirectory named dir30.

Tips

    You may want to include the -i option (for example, rm -i *) to confirm each deletion so you do not delete files by mistake.

    Since the rm command cannot remove directories without the -R option, an error message may appear when you use the rm * command string in a directory that contains subdirectories (Figure 25 ).

To remove all files & subdirectories in a directory

Type rm -R * and press (Figure 25 ).

Warning!

    This is the most dangerous command in all of Unix. If you enter this command in the root directory (/), you will erase the entire disk (if you have permission). Use this command with care!

Tip

    You may want to include the -i option (for example, rm -Ri *;

    Figure 25 ) to confirm each deletion so you do not delete files or subdirectories by mistake.

To remove an empty directory

Type rmdir

directory … and press . For example, rmdir Originals removes the subdirectory named

Originals in the current directory (Figure 26 ).

Figure 26. This example shows two attempts to delete a subdirectory. The first, using the

rmdir command, is not successful because the directory is not empty. The second, using the

rm -R command string, does the job.

Tip

    The rmdir command will result in an error message if the directory you are trying to remove is not empty (Figure 26 ).

To remove a directory & its contents

Type rm -R

directory and press . For example, rm -R Originals removes the directory named

Originals even if it is not empty (Figure 26 ).