Shell Programming and Scripting

# because windows CMD doesn't actually expand * into arguments for you
exec ./zsh.exe batmon.zsh 20[0-9][0-9]-* > events.txt 2> stats.txt

#!/bin/zsh

# Loop over all commandline parameters 2011-*
# basename strips path just leaving name of file
while [ "$#" -gt 0 ]
do
        DAY=$(./basename.exe "$1" )
        DAY="${DAY[0,4]},${DAY[6,7]},${DAY[9,10]}"

    # The datafiles contain \r, which must be stripped somehow
        while read LINE
    do
        # Convert HH:MM:SS into HH,MM,SS to make awk easier
                TIME="${LINE[5,12]}"
                TIME="${TIME[0,2]},${TIME[4,5]},${TIME[7,8]}"
                echo -e "${DAY},${LINE[0,2]},${TIME},${LINE[14,99]}\r"
    done < "$1/LogFile.txt"
    shift
done > output.txt
./gawk.exe -F "," -f batmon.awk < output.txt

exec zsh batmon.zsh 20[0-9][0-9]-* > events.txt 2> stats.txt

 
* while [ "$#" -gt 0 ] --> if argument count is greater than 0 then loop executes..so if there is an argument then go on in while loop..
so if there is any (folder) file matches pattern with "20[0-9][0-9]-*" in local dir in where script executes , then loop runs.
 
# ls -ld 20[0-9][0-9]-*
drwxr-xr-x 2 root root 4096 2011-05-20 15:16 2011-05-15 20:10:10
drwxr-xr-x 2 root root 4096 2011-05-20 14:47 2011-05-18
drwxr-xr-x 3 root root 4096 2011-05-20 15:35 2011-05-20
 
so our second script executes like this--> # ./batmon.zsh "2011-05-15 20:10:10" 2011-05-18 2011-05-20 

* ./basename.exe "$1" --> in this state , for examle our argument gets "2011-05-20" "2011-05-18" and "2011-05-15 18:00:00" if there are in there.
if you pattern like this , basename is unnecassary but i dont know about the format or i dont know what script owner intended for this.
however if our parameter "2011-20-25/20:00:00" after basename then our variable is "2011-20-25"..
 
* DAY="${DAY[0,4]},${DAY[6,7]},${DAY[9,10]}" --> this gets 0-4 and 6-7 and 9-10 chars with separated a comma.
 
* while read LINE ; do .... ; done <"$1/LogFile.txt" --> if our first argument  "2011-05-20" , 
it looks LogFile.txt in first argument dir then redirects to stdinput to LogFile.txt for while statement so all readings happens from LogFile.txt.
 
# find -type d -name "20[0-9][0-9]-*" |xargs -d'\n' ls -1
./2011-05-15 20:10:10:
LogFile.txt
./2011-05-18:
LogFile.txt
./2011-05-20:
LogFile.txt
 
# more LogFile.txt  ( all contents are completely predict )
Thu 20:10:10:0000000000000000345
Sun 22:10:10:0000000000000125651
 
 * TIME="${LINE[5,12]}"
   TIME="${TIME[0,2]},${TIME[4,5]},${TIME[7,8]}"
   echo -e "${DAY},${LINE[0,2]},${TIME},${LINE[14,99]}\r"
in this, we read a line from LogFile.txt and split format to like above and write to output.txt with 
`done > output.txt` in last line of the first while.
 
* for example if we think to read the line below
Thu 20:10:10:0000000000000000345  
   TIME="${LINE[5,12]}"  --> 20:10:10
   TIME="${TIME[0,2]},${TIME[4,5]},${TIME[7,8]}"  --> 20,10,10
   echo -e "${DAY},${LINE[0,2]},${TIME},${LINE[14,99]}\r" --> 2011-05-20,Th,20,10,10,0000000000000000345
 
* shift  --> if our arguments (parameters) are ["2011-05-15 20:10:10" 2011-05-18 2011-05-20 ] . after shift then $1 --> 2011-05-18
another shift then $1 --> 2011-05-20 and then...so it shifts the parameters to left.
 
* ./gawk.exe -F "," -f batmon.awk < output.txt --> extract lines according to batmon.awk from output.txt