use vimdiff inside while read

Shell Programming and Scripting
1

Hi,

I need to read a file name from a txt file, found the difference in two folders, then modify the file using vimdiff,

while read file
do
 diff src/$file dest/$file > /dev/null 2>&1
 if [ $? -eq 0]; then
    vimdiff src/$file dest/$file 
fi
done < ./my_text_file

since the stdin has been redirect to file my_text_file, vimdiff can't work properly.

anyone can help me to fix it?

thanks.

peter

2

Try this:

while IFS= read -r; do
  diff src/"$REPLY" dest/"$REPLY" || ( 
    exec 0< /dev/tty
    vimdiff src/"$REPLY" dest/"$REPLY" 
    )
done < infile
2 Likes
3

works like a charm

4

------------------------------------

could anyone please explain how this script work ?

5

It redirects the standard input to the controlling terminal inside the loop:

exec 0< /dev/tty

In this way the program vimdiff reads the user input instead of the stream coming from the pipe.

6

Thanks,

Could you please explain the significance of the diff command as well

diff src/"$REPLY" dest/"$REPLY" ||
 ...
7

This is a logical OR:

command1 || command2

In this case command2 will be executed only if command1 returns status different than 0 (i.e. if the files to be compared are different).

1 Like