Wow! Thanks for pointing this out. I'll do something to detect this and abort the script.

Not true in the case of all MD5 or Sha collisions but probably no practical risk.

Yes but I want to keep the first file in alphabetical basename order not alphabetical directory name order. That will require more than just the checksum command.

exec can only call a single command or script (which really slows things down with disk access) but it cannot call a function (because it looks to bulletins and $PATH to find the command)--it might work if I export the function, however. It is also subject to race conditions, while piping the completed output of find is not. However, the -type flag helps remove the if then else statement:

Code:

find "$dir" -type f | { while read -r path; do
    name=${path##*/}                                                        #basename
    sum=$(sha1sum "$path")
    echo "${sum%%' '*}"','"$name"\\"$path"                                  #sha1sum,basename\path.
done }

Is using $1 and $2 in this way robust to whitespace in the file name or path? I suspect it is not, but I don't know enough awk to be sure.

Mike