How to use the command 'mktemp' (with examples)

The ‘mktemp’ command is used to create temporary files or directories. It is particularly useful when you need to generate temporary files that are unique and won’t interfere with other existing files or directories on your system.

Use case 1: Create an empty temporary file and print its absolute path

Code:

mktemp

Motivation: In some cases, you may need to create a temporary file for testing or to store some data temporarily. By using this command, you can quickly create a unique empty temporary file without having to specify any path or name.

Explanation: This command creates a temporary file in the default temporary directory, which is usually the output of getconf DARWIN_USER_TEMP_DIR on macOS or ‘/tmp’ on other Unix-like systems. It generates a unique file name using random alphanumeric characters.

Example output:

/tmp/tmp.3uvQQ77MWT

Use case 2: Use a custom directory

Code:

mktemp --tmpdir=/path/to/tempdir

Motivation: You may want to specify a custom directory to create your temporary file in, for example, if you want to keep all your temporary files organized in a specific directory.

Explanation: The --tmpdir option allows you to specify a custom directory to create the temporary file in. In this example, “/path/to/tempdir” should be replaced with the actual path of your desired directory.

Example output:

/path/to/tempdir/tmp.CDnybZeWZj

Use case 3: Use a custom path template

Code:

mktemp /tmp/example.XXXXXXXX

Motivation: Sometimes, you need more control over the name of the temporary file. Using a custom path template allows you to define the structure and format of the file name to better suit your needs.

Explanation: By providing a specific path template as an argument, you can include static portions of the path as well as placeholders that will be replaced with random alphanumeric characters. In this example, the “X"s in the template will be replaced with random characters.

Example output:

/tmp/example.kVeXLlaD

Use case 4: Use a custom file name prefix

Code:

mktemp -t example

Motivation: If you want to create multiple temporary files with a similar name or want to signify the purpose of the temporary file, you can use a custom file name prefix.

Explanation: The -t option allows you to specify a custom file name prefix. This prefix will be included in the generated file name, followed by random alphanumeric characters.

Example output:

/tmp/tmp.examplewP1rD3Gq

Use case 5: Create an empty temporary directory and print its absolute path

Code:

mktemp --directory

Motivation: Sometimes, you may need to create a temporary directory instead of a file. This can be useful for storing multiple related temporary files or for organizing temporary data in a separate directory.

Explanation: The --directory option tells ‘mktemp’ to create a temporary directory instead of a file. The command then returns the absolute path to the newly created directory.

Example output:

/tmp/tmp.IOnSyUJ5E3

Conclusion

The ‘mktemp’ command is a powerful tool for creating temporary files and directories. Whether you need a single temporary file or an entire temporary directory, this command provides various options to customize the output and meet your specific needs. By utilizing the different options and arguments available, you can easily generate unique temporary resources for your tasks.