Run shell script in background problem

Scripting Forums AppleScript | Mac OS X
#1

In the Apple Technote TN2065 http://developer.apple.com/technotes/tn2002/tn2065.html

It states to use the syntax do shell script “command &> file_path &”

However, I would like to use a longer and variable command.

For instance previously, I would use a variable to store the commands and then do shell script.
set custom_command to " various commands "
do shell script custom_command

However, this does not work with the above syntax:

do shell script “custom_command &> file_path &”

I get the error message “sh: line 1: custom_command: command not found”

Is there a solution to this?

The reason I ask, is that I have a shell script that can take up to 20 minutes to complete and I want the user to get some feedback as to what is happening. Currently, I have the Terminal open and run the script as visual feedback, but I rather have my app show the feedback instead.

What I wanted to do was as the Technote stated:

Any ideas will be appreciated.

#2

Try something like this:

set command to "ls ~"
do shell script command & " &> ~/example.txt &"
#3

Bruce,

Thank you so much!

Now the next step… how can I read the text file and output it in relative realtime?

I tried something like this:

do shell script command & " &> ~/example.txt &"
set text_loc to ":example.txt" (EDIT: Not actual path to file, just an example)
set theText to (read file text_loc)
set content of text field "output" of window "Main" to theText

EDIT: Error fixed: (But I get a “End of file error (-39)”)

It will output to the text field once, but I would like it to continue to update the text field as the script is running and writing to the file example.txt

Any ideas?

#4

Unlike the shell, AppleScript expects colon separated paths (HFS path)


.
set text_loc to ((path to home folder as text) & "example.txt")
.
#5

Stefan,

Sorry, I was being sloppy in my example, I’m not actually using set text_loc to “~/example.txt”
The actual path was colon separated.

So that was not the source of the problem.

EDIT: I found the solution to the end of file error message. I needed to add a slight delay before having Applescript read the file.

However, I would still like to have the output be displayed in a relatively real time manner, one line at a time.

Any suggestions?

#6

None that involve AppleScript Studio.

#7

Have a look at Bruces progress bar