shell script doubt (variable pass)

[vitorgatti]

can I pass a variable to a function in shell script?

example:
#!/bin/bash
func(a)
{
echo `expr $a + 1`
}

func(3)

this is not working... :(

[Franklin52]

Here you can find how to use functions with parameters:

http://www.faqs.org/docs/abs/HTML/functions.html

Regards

[elija]

Try this

#!/bin/bash
func()
{
a = $1
echo `expr $a + 1`
}

func(3)

I have never written a shell script but Googles suggest this might work

[vitorgatti]

thanks a lot :D

the script ended like that:

#!/bin/bash
func()
{
a=$1
echo `expr $a + 1`
}

func 3

thanks again!

[i92guboj]

thanks a lot

the script ended like that:

#!/bin/bash
func()
{
a=$1
echo `expr $a + 1`
}

func 3

thanks again!

In bash I'd just do this:

#!/bin/bash
func() {
echo $(($1 + 1))
}
 
func 3

[elija]

In bash I'd just do this:

#!/bin/bash
func() {
echo $(($1 + 1))
}
 
func 3

I'm wondering if you can do something like

$1 = $1 +1

in a bash script, I am guessing not, but I am at a windows
computer now so I can't check

[i92guboj]

I'm wondering if you can do something like

$1 = $1 +1

in a bash script, I am guessing not, but I am at a windows
computer now so I can't check

The closest you can get is that that I posted above. Bash offers some basic arithmetic capabilities when you write the operations in between $((...)), the problem if that they are really limited, and *only* can use integers. So, if you need something more complete, you are bound to use something like bc, which is well known and works well.

[Franklin52]

The closest you can get is that that I posted above. Bash offers some basic arithmetic capabilities when you write the operations in between $((...)), the problem if that they are really limited, and *only* can use integers. So, if you need something more complete, you are bound to use something like bc, which is well known and works well.

An alternative is the C-style:

(($1++))

Regards