How to parse command line arguments in Bash?
Parse command line arguments in Bash
In Bash, you can use the special variables $1
, $2
, etc., to access command-line arguments passed to a script or function. These variables refer to the first, second, etc. argument passed to the script or function.
Here's an example script that uses command-line arguments:
#!/bin/bash
echo "The name of the script is $0"
echo "The first argument is $1"
echo "The second argument is $2"
echo "All the arguments are $@"
In this example, $0
refers to the name of the script, while $1
and $2
refer to the first and second arguments, respectively. The special variable $@
refers to all the arguments passed to the script.
To run this script and pass in some arguments, you can use the following command:
$ ./script.sh arg1 arg2
This would output the following:
The name of the script is ./script.sh
The first argument is arg1
The second argument is arg2
All the arguments are arg1 arg2
In addition to accessing individual command-line arguments, you can also use the getopts
command to parse command-line options and arguments. This is a more advanced technique, but it can be useful for scripts that accept many options and arguments. The getopts
command is beyond the scope of this answer, but you can refer to the Bash documentation for more information.
Related Bash Tutorials
- Dynamic variable names in Bash
- Bash and shell script variable capitalization?
- How to get the directory where a Bash script is located from within the script itself?
- Parsing JSON with Unix tools
- Command not found error in Bash variable assignment
- How to set a variable to the output of a command in Bash?
- How to run Bash commands in Python?
- Extract filename and extension in Bash?
- Looping through the content of a file in Bash
Previous Article
Golang Tutorials
- Hello World
- Operators in Go
- Declarations in Go
- Values in Go
- Variables in Go
- For in Go
- If/Else in Go
- Switch in Go
- Arrays in Go
- Slices in Go
- Maps in Go
- Range in Go
- Functions in Go
- Closures in Go
- Recursion in Go
- Pointers in Go
- Strings and Runes in Go
- Structs in Go
- Methods in Go
- Interfaces in Go
- Generics in Go
- Errors in Go
- Goroutines in Go
- Channels in Go
- Select in Go
- Timeouts in Go
- Timers in Go
- Worker Pools in Go
- WaitGroups in Go
- Mutexes in Go
- Sorting in Go
- Panic in Go
- Defer in Go
- Recover in Go
- JSON in Go
- XML in Go
- Time in Go
- Epoch in Go
- Time Formatting in Go
- Random Numbers in Go
- Number Parsing in Go
- URL Parsing in Go
- SHA256 Hashes in Go
- Base64 Encoding in Go
- Reading Files in Go
- Writing Files in Go
- File Paths in Go
- Directories in Go
- Testing and Benchmarking in Go
- Command-Line Arguments in Go
- Command-Line Flags in Go
- Command-Line Subcommands in Go
- Environment Variables in Go
- HTTP Client in Go
- HTTP Server in Go
- Context in Go
- Signals in Go