sync

Flushes all pending write operations to the appropriate disks. More information: https://www.gnu.org/software/coreutils/manual/html_node/sync-invocation.html.

• Flush all pending write operations on all disks:

sync

• Flush all pending write operations on a single file to disk:

sync {{path/to/file}}

• Flush writes and drop file system caches (Linux only):

sync; echo 3 | sudo tee /proc/sys/vm/drop_caches

• Flush disk writes and attempts to clear inactive memory and filesystem caches (macOS only):

sync; sudo purge