Creating executable files

[Jongi]

So if I create an executable file with the 1st line as:

#!/bin/sh

Does it mean that if I have it with an .sh extenion it will need me to run it with ./filename or sh filename?

And without the .sh extension I can just type filename (assuming it is in the path or current directory)?

All the above assumes the command: chmod +x filename has been run.

[jim]

yes the above is true

[Mat]

just to clarify things..


the extension is absolutely irrelevant..

you only need to care for
1. file as to be executable (chmod +x filename)
2. the interpreter (first line of the script) has to be correct



so even if the script is just called "ban.all.Users" without any extension you can still call it...

either by calling the script with its absolute path
# /usr/local/bin/myScripts/ban.all.Users

or if you're in the directory
# cd /usr/local/bin/myScripts/
# ./ban.all.Users
(note: just calling ban.all.Users will not work, even if you're in the right directory)

or by putting the scripts' parent directory into your path and just calling the script
(regardless of the current path you're in)
# ban.all.Users


Mat

[Jongi]

Mat so when does it force you to use the ./filename syntax?

[liro]

like mat wrotes, when your in the directory were the script resides....

cause otherwise if there would be another script with same name in your path environment the shell wouldn't know which it has to take (security reasons)

[Jongi]

oh. that makes sense

[JoeyJoJoe]

I don't know about your level of experience but this page was really interesting to me (it's for the very basic beginer)

http://rute.2038bug.com/node10.html.gz

[Jongi]

How would I create an executable file to mount an iso file. I want the file to execute the following:

umount /mnt/iso/
mount -t iso9660 -o loop <path to iso> /mnt/iso/

If I call the file mountiso, I would like mountiso ~/test.iso to execute the following:

umount /mnt/iso/
mount -t iso9660 -o loop ~/test.iso /mnt/iso/

So essentially I need the file to read the the arguement from the command line.

[JoeyJoJoe]

what I would do is create the mountiso.sh in your home folder, then do in the terminal:

chmod 0755 mountiso.sh

then edit the file using something like gedit, so that it looks like:

#!/bin/sh

echo "what file would you like to mount?"
read answer
umount /mnt/iso/
mount -t iso9660 -o loop $answer /mnt/iso/

that should work for you... give it a go and try and work from there. Post back if it works

[Jongi]

I thought of that. Will it be able to provide path data when I press the TAB button? If not it will be the next best alternative I suppose.

Will give it a bash shortly and report back.

[Jongi]

Yeah just tried it. As I suspected it won't allow filename completion at the prompt for the file I would like to mount, hence why I wanted it to pick up the field from the command line.

[liro]

Originally Posted by Jongi

Yeah just tried it. As I suspected it won't allow filename completion at the prompt for the file I would like to mount,...

to enable this, just rewrite the script from JoeyJoJoe:

#!/bin/sh

# check parameter
if [ -f $1 ]; then
  echo "no file to mount given, exit..."
  exit
fi

umount /mnt/iso/
mount -t iso9660 -o loop $1 /mnt/iso/

then, call the script with the argument of the file to mount.....

[ccrvic]

Originally Posted by Jongi

so when does it force you to use the ./filename syntax?

When the executable is not in a directory mentioned in $PATH.

Vic.

[Jongi]

So I the file as:

#!/bin/sh

# check parameter
if [ -f $answer]; then
  echo "no file to mount given, exit..."
  exit
fi

umount /mnt/iso/
mount -t iso9660 -o loop $answer /mnt/iso/

but if I run # ./mountiso name.iso

no file to mount given, exit...

You wrote $answer where it should have been $1.

A common typo! ;-)