SCRIPT: GrubED - GUI Grub editing

[mssever]

I've found an interesting thing... If I edit the Feisty grub menu.lst while running Gutsy, it fails in the same way. Editing the Gutsy menu.lst in Feisty works fine. So it seems it's not a difference in the menu.lst but in the implementation of grep in Gutsy.

There may well be something to that. I have a script of an entirely different nature that relies heavily on grep. After I upgraded to Gutsy, I started getting odd errors (come to think of it, my errors were bash errors, not grep errors). At any rate, I eventually did an end run around the problem by rewriting it in Ruby.

[Gina]

Yes, it could be some other bash function than grep - I'm still investigating, I'm pretty new to Linux and learning to write bash scripts. Looking into this is good practice I'm retired so don't have work as a time restraint

[Gina]

I think the problem is in either grep of the pipe function though both seem fine everywhere but one line :- MENU_ITEM=$(grep ^title $G_MENU | grep -n $OS_SEL$ | grep -o ^[[:digit:]]*)

In particular under Gutsy $(grep ^title $G_MENU | grep -n $OS_SEL$) returns no string when used in an echo command, so filtering to show only the line number digits also produces nothing and hence a MENU_ITEM of zero. $OS_SEL is correct and grep ^title $G_MENU has been used before.. Running under Feisty procuces the expected results and everything works fine.

(Hope I'm not "treading on any toes" in posting this and that it may be some help)

[mssever]

I think the problem is in either grep of the pipe function though both seem fine everywhere but one line :- MENU_ITEM=$(grep ^title $G_MENU | grep -n $OS_SEL$ | grep -o ^[[:digit:]]*)

In particular under Gutsy $(grep ^title $G_MENU | grep -n $OS_SEL$) returns no string when used in an echo command, so filtering to show only the line number digits also produces nothing and hence a MENU_ITEM of zero. $OS_SEL is correct and grep ^title $G_MENU has been used before.. Running under Feisty procuces the expected results and everything works fine.

I wonder if switching to egrep would help. When using regular expressions that contain anything other than alphanumerics, I always use egrep instead of grep, since egrep produces better results.

[Tomosaur]

Yeah, egrep is definitely a possibility, but I'm keeping my options open for now. I may just switch to sed and be done with it - the current search and replace is more complicated than it needs to be to be honest, I'm just very stubborn

[Gina]

I think I've got something working in Gutsy. It's a little less tidy than the original in that I'm displaying numbers in the OS list. Try as I might, I can't get grep to search correctly on the string returned by zenity from the OS list. However, I'm pretty new to bash scripting and may have missed something. Also I expect my new bit could be made shorter.

list_menu(){
#List a menu of installed operating systems. Double click to set default.
grep ^title $G_MENU  > $AVAIL
grep ^title $AVAIL | grep -n ^title > $AVAIL
cat $AVAIL | sed '/Other operating systems/ d' | sed 's/:title	/ /' > $AVAIL # Remove unwanted line
OS_SEL=$(cat $AVAIL | zenity --list --width=400 --height=200 --title="Available Menu Items" --column "Operating Systems" --text="Choose an OS:")
if [ -n "$OS_SEL" ]
then
  MENU_ITEM=$(echo $OS_SEL | grep -o ^[[:digit:]]*) # Strip OS number off
  let MENU_ITEM=$MENU_ITEM-1
  DEF_LINE=$(grep  -n ^default $G_MENU | grep -o ^[[:digit:]]*)
  DEF_CURR=$(grep ^default $G_MENU | grep -o [[:digit:]]*$)
  vi -e -c "$DEF_LINE"s/"$DEF_CURR"/"$MENU_ITEM" $G_MENU -c :wq | zenity --progress --pulsate --auto-close --title="New Default" --text="Progress:"
  success
fi
rm $AVAIL
}

[Tomosaur]

I think I've got something working in Gutsy. It's a little less tidy than the original in that I'm displaying numbers in the OS list. Try as I might, I can't get grep to search correctly on the string returned by zenity from the OS list. However, I'm pretty new to bash scripting and may have missed something. Also I expect my new bit could be made shorter.

list_menu(){
#List a menu of installed operating systems. Double click to set default.
grep ^title $G_MENU  > $AVAIL
grep ^title $AVAIL | grep -n ^title > $AVAIL
cat $AVAIL | sed '/Other operating systems/ d' | sed 's/:title    / /' > $AVAIL # Remove unwanted line
OS_SEL=$(cat $AVAIL | zenity --list --width=400 --height=200 --title="Available Menu Items" --column "Operating Systems" --text="Choose an OS:")
if [ -n "$OS_SEL" ]
then
  MENU_ITEM=$(echo $OS_SEL | grep -o ^[[:digit:]]*) # Strip OS number off
  let MENU_ITEM=$MENU_ITEM-1
  DEF_LINE=$(grep  -n ^default $G_MENU | grep -o ^[[:digit:]]*)
  DEF_CURR=$(grep ^default $G_MENU | grep -o [[:digit:]]*$)
  vi -e -c "$DEF_LINE"s/"$DEF_CURR"/"$MENU_ITEM" $G_MENU -c :wq | zenity --progress --pulsate --auto-close --title="New Default" --text="Progress:"
  success
fi
rm $AVAIL
}

Yeah, it definitely seems to be a problem with grep. I've tried every grep-oriented solution I can think of and nothing seems to work right. I think sed is the way forward for now, to be honest.

[Gina]

I've now tested my modifications on the real GrubEd in Gutsy and it seems to work fine. Most of the other functions work fine except the Direct Edit. I think the trouble here is the patch command but not investigated it yet. The Desktop Launcher doesn't work in Gutsy - have to use the Terminal.

I've also tested it in Feisty and all fine.

[Gina]

A bit later... re Direct Edit :-

Yes, it seems the patch command doesn't work properly in Gutsy Editing works if cp is used instead of patch. - copying the output from zenity back into menu.lst.

BTW Restore doesn't work in Gutsy as it does in Feisty and again I think the patch command is responsible.

[Tomosaur]

Ok, thanks for the heads up. Direct Edit and Backup / Restore seem to work fine for me on Gutsy :S Have you used a different version of patch or anything like that?