Question

I am working on a UNIX task where i want check if a particular log file is present in the directory or not. If it is present, i would like to rename it by appending a timestamp at the end. The format of the file name is as such: ServiceFileName_0.log

This is what i have so far but it wouldn’t rename when i run the script, even though there is a file with the name ServiceFileName_0.log present.

renameLogs()
{
   #If a ServiceFileName log exists, rename it

   if [ -f $MY_DIR/logs/ServiceFileName_0.log ]; 
   then
    mv ServiceFileName_0.log ServiceFileName_0.log.%M%H%S
   fi
}

Pls Help!

Thanks

Answer 1

renameLogs()
{
    if [ -f $MY_DIR/logs/ServiceFileName_0.log ] 
    then mv $MY_DIR/ServiceFileName_0.log $MY_DIR/ServiceFileName_0.log.$(date +%M%H%S)
    fi
}

Use the directory prefix consistently. Also you need to specify the time properly, as shown.

Better, though (less repetition):

renameLogs()
{
    logfile="$MY_DIR/logs/ServiceFileName_0.log"
    if [ -f "$logfile" ] 
    then mv "$logfile" "$logfile.$(date +%H%M%S)"
    fi
}

NB: I’ve reordered the format from MMHHSS to the more conventional HHMMSS order. If you work with date components too, you should seriously consider using the ordering recommended by ISO 8601, which is [YYYY]mmdd. It groups all the log files for a month together in an ls listing, which is usually helpful. Using ddmm order means that the files for the first of each month are grouped together, then the files for the second of each month, etc. This is usually less desirable.