File manager (copy operation) basics

Just learned that my file manager (Thunar) pastes files in the order they were sorted the moment you marked and copied them, no matter if you change the sort order in the destination directory (after you've marked files for copying). Also learned that when Thunar sees that there's no more disk space in the destination directory, it doesn't always skip files but sometimes pastes the last file partly. Thunar copies as many files, and as much of them as it can fit before the space completely runs out.

This is probably basic computing but still nice to confirm it. I guess most file managers and shell commands work like this.

When running two parallel copy operations to the same disk, the priority seems to be random. Sometimes the first copy gets the larger last file, and sometimes the second copy gets the larger last file. Sometimes one of them skips a file completely.

I guess it checks inbetween every file, during the copy operation, whether or not there's enough free space. If there isn't, Thunar won't bother trying to copy the next file. If the space runs out before Thunar has a chance to check free space the last file gets partly written.


# Makes 90 files named test#, the number corresponds to the size of the file in MB.
for n in {0..90}; do dd if=/dev/zero of=test$n bs=1M count=$n; done

# Run a loop that lists the content of destination dir while Thunar is copying the files.
for n in {0..900}; do sleep 0.1; echo "***"; ls; done