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MD5Sum List Script
#This script takes a newline delimited file list from STDIN for md5 hashing
#This script requires the `md5sum`, `pv`, `paste`, `bc`, and 'numfmt' commands

#The output of the md5s are stored in the file specified by the first parameter
#The format for each md5 hash to the output file is "$FileName\t$Hash\n"

#File sizes are always output in megabytes with 3 decimal places
#While calculating the hashes the script keeps the user informed of the progress of both the current file and all the files as follows:
#1) "Hashing: $FileName ($FileSize MiB)\n"
#2) The progress of the hash of the file ran through `pv`, with the size precalculated for file progress percents
#3) "Finished $TotalProgressPercent% ($ProcessedBytes/$TotalBytes MiB)\n\n"

#Get $Outfile from the first argument and the $FileList from STDIN (newline delimited)
FileList=`cat /dev/stdin`

#Format a byte count in MegaBytes with comma grouping and 3 decimal places
MbFmtNoExt ()
	echo "scale=3; $1/1024/1024" | bc | echo -n `xargs numfmt --grouping`

#Add " MiB" to the end of MbFmtNoExt
MbFmt ()
	echo `MbFmtNoExt $1`" MiB"

#Calculate and output the total size of the file list
echo -n "Calculating total size: "
TotalSize=`echo "$FileList" | xargs -d"\n" stat --printf="%s\n" | paste -s -d+ | bc`
MbFmt $TotalSize
echo #Add an extra newline

#Run over the list (newline delimited)
for FileName in `echo "$FileList"`
	#Output the file size and name to STDOUT
	FileSize=`stat --printf="%s" "$FileName"`
	echo "Hashing: $FileName ("`MbFmt $FileSize`")"

	#Output the filename to $OutFile
	echo -n $FileName$'\t' >> $OutFile

	#Run the md5 calculation with `pv` progress
	#Output the hash to $OutFile after the FileName and a tab
	cat "$FileName" | pv -s $FileSize | md5sum | awk '{print $1}' >> $OutFile

	#Output the current progress for the entire file list
	#Format: "Finished $TotalProgressPercent% ($ProcessedBytes/$TotalBytes MiB)\n\n"
	echo -n "Finished "
	printf "%.3f" `echo "scale=4; $CalculatedBytes*100/$TotalSize" | bc`
	echo "% ("`MbFmtNoExt $CalculatedBytes`"/"`MbFmt $TotalSize`$')\n'
Auto Locking Windows on Login

On my primary computer (whose harddrive is encrypted) I always have Windows auto logging in to help with the bootup time. However, my bootup time can be rather slow; and if I needed to have my computer booted but locked, I had to wait for the login to complete so I could lock the computer. This has been becoming a nuisance lately when I need to get out of my house quickly in the morning.

For the solution I created a windows boot entry that auto locks the computer after logging the user in. This also requires a batch file, to run for the user on startup, to detect when this boot entry was selected. Here are the steps to create this setup:

  1. Create the new boot entry: In the windows command line, run: bcdedit /copy {current} /d "Lock on Startup"
    This creates a new boot option, duplicated from your currently selected boot option, in the boot menu labeled “Lock on Startup”.
  2. (Optional) Change the bootup timeout: In the windows command line, run: bcdedit /timeout 5
    Where 5 is a 5 second timeout.
  3. Create a batch file to run on login: In your start menu’s startup folder, add a batch file. You can name it anything as long as the extension is “.bat”.
    Add the following to the file: bcdedit /enum {current} | findstr /r /c:"description *Lock on Startup" && rundll32.exe user32.dll,LockWorkStation
    Note that there are 2 spaces in the description search string to replicate the regular expression's 1 or more quantifier “+”, since findstr only supports the 0 or more quantifier “*”.