Bash program, grep returning No such file or directory

NashChap · 10-09-2013, 04:37 PM

I am writing a recycle bin program for work (unix training) where it has to mimic the rm command but instead of deleting, move into a new folder named delete, whilst adding on the iode of the file/dir onto the end and recording the original name and path in a separate file named .restore.info for when the file needs to be restored.

Code:

  1 #!/bin/bash
  2
  3 WHERE=$(grep $1 ~/.restore.info | cut -d: -f2)
  4
  5 ONAME=$(grep $1 ~/.restore.info | cut -d_ -f1)
  6
  7
  8 echo " this is the home $HOME"
  9 echo " the original location $WHERE "
 10 #echo " the original name $ONAME"
 11
 12 restore(){
 13 #if the file does NOT exist
 14 if [ ! -f ./safe_rm_restore/$1 ]
 15 then
 16         echo "$1 not found!"
 17
 18 #if the file DOES exist
 19 else
 20         print "Do you want to overwrite $1 ?"
 21         read answer
 22
 23 answer=$(echo $response | cut -c1)
 24
 25 if [[ $answer = "y" || $answer = "Y" ]]
 26 then
 27
 28         mv $HOME/deleted/$1 $WHERE
 29
 30         fi
 31
 32         if [[ $answer = "n" || $answer = "N" ]]
 33
 34         then
 35
 36         echo "file has not been restored"
 37
 38         fi
 39
 40 fi
 41
 42 }

this is my code for the restore portion of the task but whenever i run it it nothing returns

i thought it may be something to do with my grep so i did grep ~/.restore.info PRACTICE_23116842 to see if it works and it just returned "No such file or directory", but i can actually see the file manually....

i have no idea what im doing wrong haha

thanks in advance for the help

MensaWater · 10-09-2013, 04:55 PM

In your manual command you have the grep in wrong order:
grep ~/.restore.info PRACTICE_23116842
It should be:
grep PRACTICE_23116842 ~/.restore.info

In your code you have $1 for file name - are you passing that in on invocation (i.e. restore.sh PRACTICE_23116842)? You should be aware that positional parameters are relative to the last command so while your command:
WHERE=$(grep $1 ~/.restore.info | cut -d: -f2)
Might work with the file name PRACTICE_23116842 being $1 the next command might NOT work.
The usual practice is to set the passed in parameters to something unique within the program e.g.

DELFILE=$1
WHERE=$(grep $DELFILE ~/.restore.info | cut -d: -f2)
ONAME=$(grep $DELFILE ~/.restore.info | cut -d_ -f1)

Also you should be aware that "where" is a keyword in many things so you really ought to use something different (i.e. LOCATION) just to avoid confusion.

SAbhi · 10-09-2013, 09:52 PM

well i dont understand the complete thing.. but it is always advisable to store arguments in a variable & then to proceed further... and this doesnt looks like a problem here..

where does it says an error:

Code:

bash -x [filename.sh]

Quote:

print "Do you want to overwrite $1 ?"
21 read answer
22
23 answer=$(echo $response | cut -c1)

Also.. the above looks incorrect to me!!! it should be something like:

Code:

response=$(echo $answer |cut -c1)
if [[ $response = "y" || $response = "Y" ]]
then
do_something
else
nested_if_if_required
do_something
fi

Quote:

grep ~/.restore.info PRACTICE_23116842

it should be: $grep [pattern] [filename/location]

grail · 10-10-2013, 03:07 AM

Maybe you could show the call to the restore function as well seeing it is being passed a parameter.

I have also noticed a distinct lack of quoting ... are we to assume that all files being moved to the trash will never contain whitespace or other unusual characters?