Gnu/coreutils/Disk-usage

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14 Disk usage

No disk can hold an infinite amount of data. These commands report how much disk storage is in use or available, report other file and file status information, and write buffers to disk.

df invocation    Report file system disk space usage.
du invocation    Estimate file space usage.
stat invocation    Report file or file system status.
sync invocation    Synchronize cached writes to persistent storage.
truncate invocation    Shrink or extend the size of a file.