What is use of 1 in shell script?
1 is located to parameter ‘s position, and “$@” is located to the word ‘s one. If $1 is defined, evaluate “$@” . This expression can be used in the not only Bourne shell, but also Bourne Again Shell (Bash).
What is $1 in a shell script?
$1 is the first command-line argument passed to the shell script. $0 is the name of the script itself (script.sh) $1 is the first argument (filename1) $2 is the second argument (dir1)
What is $@ in shell?
$@ refers to all of a shell script’s command-line arguments. $1 , $2 , etc., refer to the first command-line argument, the second command-line argument, etc. Letting users decide what files to process is more flexible and more consistent with built-in Unix commands.
Which is the first argument in a shell script?
$1 is the first command-line argument passed to the shell script. Also, know as Positional parameters. For example, $0, $1, $3, $4 and so on. If you run ./script.sh filename1 dir1, then: $0 is the name of the script itself (script.sh)
What does$ 0 mean in shell script?
These are positional arguments of the script. If you execute ./script.sh, $0 will give output ./script.sh but if you execute it with bash script.sh it will give output script.sh. They are called the Positional Parameters. A positional parameter is a parameter denoted by one or more digits, other than the single digit 0.
What does file descriptor 1 mean in Bash?
File descriptor 1 is the standard output ( stdout ). File descriptor 2 is the standard error ( stderr ). Here is one way to remember this construct (although it is not entirely accurate): at first, 2>1 may look like a good way to redirect stderr to stdout.
How to calculate the number of arguments in script.sh?
If you run ./script.sh filename1 dir1, then: 1 $0 is the name of the script itself (script.sh) 2 $1 is the first argument (filename1) 3 $2 is the second argument (dir1) 4 $9 is the ninth argument 5 $ {10} is the tenth argument and must be enclosed in brackets after $9. 6 $ {11} is the eleventh argument.