Bash: Create hardlink if destination is inside same volume, copy if not -

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Bash: Create hardlink if destination is inside same volume, copy if not -

my bash script makes copies of files multiple directories.

in order save space , maximize speed, prefer create hardlinks instead of copies, since copies need remain identical during life anyway.

the script ran in different computers, though, , there may case destination directory exists in different volume origin's. in such case, cannot create hardlink , need re-create file.

how check if origin , destination directory exist in same volume, either hard link or re-create depending on it?

a simple way so, seek both:

ln "$from" "$to" || cp "$from" "$to"

depending upon purposes, creating reference re-create (which lightweight hardlinked file, allows 2 copies edited/diverge in future) might work:

cp --reflink=auto "$from" "$to"

but, can obtain device filesystem's device id using stat:

if [ $(stat -c %d "$from") = $(stat -c %d "$target_dir") ]; ln "$from" "$target_dir"/ else cp "$from" "$target_dir"/ fi

bash volume hardlink

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