$ curl cheat.sh/

# fallocate
# Reserve or deallocate disk space to files.
# The utility allocates space without zeroing.
# More information: <https://manned.org/fallocate>.

# Reserve a file taking up 700 MiB of disk space:
fallocate --length 700M path/to/file

# Shrink an already allocated file by 200 MiB:
fallocate --collapse-range --length 200M path/to/file

# Shrink 20 MB of space after 100 MiB in a file:
fallocate --collapse-range --offset 100M --length 20M path/to/file

$

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