“dirname” is a command-line utility that calculates and outputs the parent directory of a given file or directory path. Its primary purpose is to extract the directory portion of a path, excluding the filename or the last component of the path.
When provided with a file or directory path as an argument, “dirname” parses the path and returns the parent directory component. It identifies the portion of the path that precedes the last forward slash (“/”) or backslash (“”) character, depending on the operating system.
The output of “dirname” is the directory path without the filename or the last component. This can be useful in various scenarios, such as script automation, file manipulation, or when working with file paths in general. By using “dirname,” users can easily isolate the directory part of a path for further processing or to perform operations specifically on the parent directory.
For example, if given the path “/home/user/documents/file.txt,” the “dirname” command would return “/home/user/documents,” as it identifies and extracts the parent directory portion of the path.
“dirname” can be particularly handy when used in conjunction with other shell commands or scripts that require working with file paths. It allows users to extract the directory component dynamically, regardless of the specific filename or the structure of the path.
It’s important to note that “dirname” does not validate the existence or accessibility of the directory path it outputs. It simply calculates the parent directory based on the provided path. Therefore, the output of “dirname” may still refer to a non-existent or inaccessible directory.
dirname Command Examples
1. Calculate the parent directory of a given path:
# dirname /path/to/file_or_directory
2. Calculate the parent directory of multiple paths:
# dirname /path/to/file_a /path/to/directory_b
3. Delimit output with a NUL character instead of a newline (useful when combining with xargs):
# dirname --zero /path/to/directory_a p/ath/to/file_b
Summary
In summary, “dirname” is a command-line utility that calculates the parent directory of a given file or directory path. By extracting the directory portion and excluding the filename or the last component, “dirname” provides a convenient way to isolate and work with the parent directory part of a path. This functionality is useful in various scripting or file manipulation scenarios where the parent directory needs to be referenced or operated upon.