Shell Programming and Scripting

I have a script that reads a file then moves all the files that are listed within that file.

So read file A then copy all files that are listed within.

I have the script append a log everytime a file is moved.

My issue is that it's appending the log even though the file was not found.

here's part of my script

Code:

 cat /path/to/file/$file1 | while read a
do
  var1=`echo "$a"`
  mv /path/to/data/'$var1' /path/to/new/location
echo "Moved File" $var1 >> /path/to/file/logs/filesmoved$year$month$day.txt
done < /path/to/file/$file1

I see error msg mv: cannot access /path/to/data/$var1: No such file or directory (error 2)

how do I get my script to read that error msg. or does it put it to a variable by default?

Once I find that out I can make a test condition before writing to the log.

Thanks

cat /path/to/file/$file1 | while read a
do
var1=`echo "$a"`
mv /path/to/data/'$var1' /path/to/new/location

if [ $? -eq 0 ]
then
echo "Moved File" $var1 > /path/to/file/logs/filesmoved$year$month$day.txt
fi

done < /path/to/file/$file1

very simple

mv /path/to/data/'$var1' /path/to/new/location 2>/dev/null

However, it is always a good practice to log all kind of messages in your log. This can help you find if anything is messed up.

I guess you must be knowing about redirection, but still since this question is related to that let me explain what exactly the 2>/dev/null do

well 2 stands for the file descriptor, standard errors. so any errors that are directed to standard error are written in file descriptor 2. by doing 2> you are asking to redirect the standard errors. /dev/null is a null device. so 2>/dev/null is instructing to direct standard errors to a null device instead of the console or your error log

other standard file descriptors are
0 standard output
1 standard input

one more remark i feel "done < /path/to/file/$file1" is redundant, you may discard it as well since you are already doing a "cat < /path/to/file/$file1"


let me make this a bit more straight, (if i havent misinterpreted what you intend to do)

cat /path/to/file/$file1 | while read a
do
mv /path/to/data/"$a" /path/to/new/location 2>/dev/null
echo "Moved File" $a" >>/path/to/file/logs/filesmoved$year$month$day.txt 2>/dev/null
done

Try to change your script as follows:

while read a
do
var1=`echo "$a"`
mv /path/to/data/"$var1" /path/to/new/location #Use double quote
echo "Moved File" $var1 >> /path/to/file/logs/filesmoved$year$month$day.txt
done < /path/to/file/$file1 # No need to cat file in first line if you have this line.