You can pass more than one argument to your bash script. In general, here is the syntax of passing multiple arguments to any bash script: script.sh arg1 arg2 arg3 … The second argument will be referenced by the $2 variable, the third argument is referenced by $3 , .. etc.
bash [filename] runs the commands saved in a file. $@ 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. Place variables in quotes if the values might have spaces in them.
There is no difference if you do not put $* or $@ in quotes. But if you put them inside quotes (which you should, as a general good practice), then $@ will pass your parameters as separate parameters, whereas $* will just pass all params as a single parameter.
$1 is the first argument (filename1) $2 is the second argument (dir1) $9 is the ninth argument.
Use "$@"
instead of plain $@
if you actually wish your parameters to be passed the same.
Observe:
$ cat no_quotes.sh
#!/bin/bash
echo_args.sh $@
$ cat quotes.sh
#!/bin/bash
echo_args.sh "$@"
$ cat echo_args.sh
#!/bin/bash
echo Received: $1
echo Received: $2
echo Received: $3
echo Received: $4
$ ./no_quotes.sh first second
Received: first
Received: second
Received:
Received:
$ ./no_quotes.sh "one quoted arg"
Received: one
Received: quoted
Received: arg
Received:
$ ./quotes.sh first second
Received: first
Received: second
Received:
Received:
$ ./quotes.sh "one quoted arg"
Received: one quoted arg
Received:
Received:
Received:
For bash and other Bourne-like shells:
java com.myserver.Program "$@"
Use "$@"
(works for all POSIX compatibles).
[...] , bash features the "$@" variable, which expands to all command-line parameters separated by spaces.
From Bash by example.
I realize this has been well answered but here's a comparison between "$@" $@ "$*" and $*
Contents of test script:
# cat ./test.sh
#!/usr/bin/env bash
echo "================================="
echo "Quoted DOLLAR-AT"
for ARG in "$@"; do
echo $ARG
done
echo "================================="
echo "NOT Quoted DOLLAR-AT"
for ARG in $@; do
echo $ARG
done
echo "================================="
echo "Quoted DOLLAR-STAR"
for ARG in "$*"; do
echo $ARG
done
echo "================================="
echo "NOT Quoted DOLLAR-STAR"
for ARG in $*; do
echo $ARG
done
echo "================================="
Now, run the test script with various arguments:
# ./test.sh "arg with space one" "arg2" arg3
=================================
Quoted DOLLAR-AT
arg with space one
arg2
arg3
=================================
NOT Quoted DOLLAR-AT
arg
with
space
one
arg2
arg3
=================================
Quoted DOLLAR-STAR
arg with space one arg2 arg3
=================================
NOT Quoted DOLLAR-STAR
arg
with
space
one
arg2
arg3
=================================
A lot answers here recommends $@
or $*
with and without quotes, however none seems to explain what these really do and why you should that way. So let me steal this excellent summary from this answer:
+--------+---------------------------+
| Syntax | Effective result |
+--------+---------------------------+
| $* | $1 $2 $3 ... ${N} |
+--------+---------------------------+
| $@ | $1 $2 $3 ... ${N} |
+--------+---------------------------+
| "$*" | "$1c$2c$3c...c${N}" |
+--------+---------------------------+
| "$@" | "$1" "$2" "$3" ... "${N}" |
+--------+---------------------------+
Notice that quotes makes all the difference and without them both have identical behavior.
For my purpose, I needed to pass parameters from one script to another as-is and for that the best option is:
# file: parent.sh
# we have some params passed to parent.sh
# which we will like to pass on to child.sh as-is
./child.sh $*
Notice no quotes and $@
should work as well in above situation.
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