Other File Operations

cat

Syntax :

- cat [file....] - Concatenate and display the contents of files(s)

Examples:

# cat test.sh
Concatenate and display the contents of file "test.sh"

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Syntax:

- more [filename].... - Display one screen at a time

Examples:

# more test.sh

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Display the contents of file "test.sh"

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cp

Syntax :

- cp [-i] file1 new_file - Copy a file

- cp [-i] file [file...] dest_dir - Change file group

- cp -r [-i] dir [dir...] dest_dir - Copy directories

Examples:

% ls
ll.sh newfile smit.log

% cp ll.sh ll.sh.new
% ls
ll.sh ll.sh.new newfile smit.log

Description :

-i : Prompts it with the name of a file to be overwritten. This occurs if the TargetDirectory or TargetFile parameter contains a file with the same name as a file specified in the SourceFile or SourceDirectory parameter. If we enter y or the locale's equivalent of y, the cp command continues. Any other answer prevents the cp command from overwriting the file.

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mv

Syntax :

- mv [-i] file new_file - Rename a file

- mv [-i] file [file....] dest_dir - Move files to a directory

- mv [-i] dir [dir...] dest_dir - Rename or move directories

Examples:

- #mv file1 new-file

Move file1 to a new or existing file (new-file)

- #mv file1 dest-directory

Move file1 to an existing directory (dest-directory)

- # mv old-filename new-filename

Rename a file in the current directory

Description :

-i : Prompts it before moving a file or directory to and existing path name by displaying the name of the file followed by a question mark. If we answer with a line starting with y or the locale's equivalent of a y, the move continues. Any other reply prevents the move from occurring.

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rm

Syntax:

- rm [-if] filename [filename...] - Remove files

- rm -r [if] dirname [filename...] - Remove directories

Examples :

# rm test.sh

Remove the file "test.sh"

# rm -r hello

Remove the directory "hello"

Notice: This command is a dangerous operation that cannot be recovered, option -i is strongly suggested.

-f : Force each file or directory to be removed without prompting for confirmation, regardless of the permissions of the entry.
-i : Write a prompt to standard error requesting confirmation before removing each entry. This option ignores any previous occurrence of the -f option.
It is strongly suggested to use the option " -i" when a user uses the command "rm" to delete a directory without mistake.

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ln

Syntax :

- ln source_file new_file - Link to a file

- ln source_file [source_file...] dest_dir - Link files to a directory

- ln [-s] source_dir linkfile - Create a symbolic link

Examples:

Description :

-s : Create a symbolic link
If the -s option is used with two arguments, target may be an existing directory or a non-existing file.If target already exists and is not a directory, an error is returned. source_file may be any path name and need not exist. If it exists, it may be a file or directory and may reside on a different file system from target. If target is an existing directory, a file is created in directory target whose name is source_file or the last component of source_file. This file is a symbolic link that references source_file. If target does not exist, a file with name target is created and it is a symbolic link that references source_file.
If the -s option is used with more than two arguments, target must be an existing directory or an error will be returned. For each source_file, a link is created in target whose name is the last component of source_file, each new source_file is a symbolic link to the original source_file. The files and target may reside on different file systems.

Hard links Vs soft links

Hard links : A hard link is a pointer to the file's i-node. For example, suppose that we have a file : a-file.txt that contains the string : "The file a-file.txt" :