Exit bash script on error in loop

[Tony Arnold]

Johnny,

Do you just echo a percentage of progress number to the progress
process, i.e., a number between 0 and 100? Why not just echo 100 just
before the exit statement. Won't that kill the progress bar too? You
will need the --auto-close option, which you have anyway!

Just a thought.

Regards,
Tony.

On 12/09/13 22:40, Johnny Rosenberg wrote:
> Okay, now that I found that the pipe was causing the problem, I also
> found the answer: PIPESTATUS. See below…
> 
> 
> 2013/9/12 Johnny Rosenberg <gurus.knugum at gmail.com
> <mailto:gurus.knugum at gmail.com>>
> 
>     2013/9/12 Tony Arnold <tony.arnold at manchester.ac.uk
>     <mailto:tony.arnold at manchester.ac.uk>>
> 
>         Johnny,
> 
>         On 12/09/13 19:19, Johnny Rosenberg wrote:
>         >
>         > I can't make exit work as I thought it would work…
>         >
>         > #!/bin/bash
>         >
>         > Title="Error"
>         > ERROR="Something bad happened."
>         >
>         > while [ something ]; do
>         >     if [[ something_bad ]]; then
>         >         yad --title "${Title}" \
>         >             --image=error \
>         >             --text "${ERROR}" \
>         >             --no-buttons \
>         >             --timeout 5 &
>         >         exit 1
>         >     fi
>         > done
>         > more_statements
>         >
>         > # End of code
>         >
>         > The problem is that even if something_bad happens,
>         more_statements are
>         > executed. The yad error messages is displayed as expected, though.
>         >
>         > (yad is a dialogue, similar to zenity, or even a zenity fork,
>         I think –
>         > yad=Yet Another Dialogue)
>         >
>         > So it seems like only the loop is exited when exit 1 is
>         executed, not
>         > the whole script. So how can I exit the whole script if
>         something bad
>         > happens inside a loop? I'd prefer a solution that doesn't make it
>         > necessary to rewrite the script from scratch…
> 
>         Odd. The following works for me. I'm on 13.04. Cannot find yad
>         in the
>         repositories. Where did you get it from?
> 
> 
>     I don't remember, but I think I compiled it from source.
>      
> 
>         And are you definitely using
>         bash for your script?
> 
> 
>     I'm on Ubuntu 12.04 and I didn't change anything like that.
>      
> 
> 
>         #!/bin/bash
> 
>         i=4
>         while [ "$i" -gt "0" ]; do
>             echo "$i - Hello"
>             if [ "$i" -eq "2" ]; then
>                 zenity --error --text "Oh no! i=3"
>                 exit 1
>             fi
>             let i=i-1
>         done
>         echo "Oops!"
> 
> 
> 
>     This one works for me too. I also replaced zenity with yad, and it
>     still works.
> 
>     I did some more experiments and I found that it's my pipe to a yad
>     progress bar that cause the problem. Unfortunately I didn't include
>     it in my example, but here's another example, which I included in a
>     reply to another reply:
> 
>     #!/bin/bash
> 
>     WaitTime=10
>     TargetPath="This/path/does/not/exist"
> 
>     if [ ! -e "${TargetPath}" ]; then
>         Time=0
>         StartTime=$(date +%s%N)
> 
>         while [ ! -e "${TargetPath}" ]; do
>             sleep .1
>             Time=$(($(date +%s%N)-StartTime))
>             if [[ Time -ge WaitTime*10**9 ]]; then
>                 yad --title "Folder missing" \
>                     --image=error \
>                     --text "Your device is not connected." \
>                     --no-buttons \
>                     --timeout 5
>                 exit 1
>             fi
>             echo "$((Time/10**7/WaitTime))"
>             Seconds=$((WaitTime-Time/10**9))
>             MM=$((Seconds/60))
>             SS=$((Seconds-MM*60))
>             echo \#$(printf "%s %d:%02d." "Time to connect your device:"
>     "$MM" "$SS")
>         done | \
>         yad --progress \
>             --title="Folder missing" \
>             --image=time \
>             --percentage=0 \
>             --auto-close
>     fi
> 
> 
> Now, it seems like I need to check for the pipe status, for instance:
> [[ PIPESTATUS[0] -ne 0 ]] && exit ${PIPESTATUS[0]}
> 
> or
> 
> [ ${PIPESTATUS[0]} -ne 0 ] && exit ${PIPESTATUS[0]}
> 
> or
> 
> [[ PIPESTATUS[0] != 0 ]] && exit ${PIPESTATUS[0]}
> 
> or
> 
> [[ PIPESTATUS[0] ]] && exit ${PIPESTATUS[0]}
> 
> and so on…
> 
> Thanks for replying and making me think in the right direction!
> 
> 
> Johnny Rosenberg
>  
> 
> 
>     yad --image="info" \
>         --title="Another dialogue" \
>         --text="You shouldn't see this dialogue"
> 
>     # End of code
> 
>     Remove the yad progress thing and it works. The problem is that I
>     WANT the progress thing…
>     So I guess the pipe is the problem here somehow, but how and what to
>     do about it?
> 
> 
>     Johnny Rosenberg
>      
> 
> 
> 
>         Regards,
>         Tony.
>         --
>         Tony Arnold,                        Tel: +44 (0) 161 275 6093
>         <tel:%2B44%20%280%29%20161%20275%206093>
>         Head of IT Security,                Fax: +44 (0) 705 344 3082
>         <tel:%2B44%20%280%29%20705%20344%203082>
>         University of Manchester,           Mob: +44 (0) 773 330 0039
>         <tel:%2B44%20%280%29%20773%20330%200039>
>         Manchester M13 9PL.                 Email:
>         tony.arnold at manchester.ac.uk <mailto:tony.arnold at manchester.ac.uk>
> 
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> 
> 
> 
> 

-- 
Tony Arnold,                        Tel: +44 (0) 161 275 6093
Head of IT Security,                Fax: +44 (0) 705 344 3082
University of Manchester,           Mob: +44 (0) 773 330 0039
Manchester M13 9PL.                 Email: tony.arnold at manchester.ac.uk