c - Is write/fwrite guaranteed to be sequential? -


is data written via write (or fwrite) guaranteed persisted disk in sequence manner? in particular in relation fault tolerance. if system should fail during write, behave though first bytes written first , writing stopped mid-stream (as opposed random blocks written).

also, sequential calls write/fwrite guaranteed sequential? according posix find call read guaranteed consider previous write.

i'm asking i'm creating fault tolerant data store persists disks. logical order of writing such faults won't ruin data, if logical order isn't being obeyed have problem.

note: i'm not asking if persistence guaranteed. if calls write persist obey order in write.

the posix docs write() state "if o_dsync bit has been set, write i/o operations on file descriptor shall complete defined synchronized i/o data integrity completion". presumably, if o_dsync bit isn't set, synchronization of i/o data integrity completion unspecified. posix says "this volume of posix.1-2008 silent effects of application-level caching (such done stdio)", think there no guarantee fwrite().


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