FileSetContentsFlags

Added in version 2.66.

class FileSetContentsFlags

Flags to pass to file_set_contents_full() to affect its safety and performance.

Fields

class FileSetContentsFlags
CONSISTENT

Guarantee file consistency: after a crash, either the old version of the file or the new version of the file will be available, but not a mixture. On Unix systems this equates to an fsync() on the file and use of an atomic rename() of the new version of the file over the old.

DURABLE

Guarantee file durability: after a crash, the new version of the file will be available. On Unix systems this equates to an fsync() on the file (if CONSISTENT is unset), or the effects of CONSISTENT plus an fsync() on the directory containing the file after calling rename().

NONE

No guarantees about file consistency or durability. The most dangerous setting, which is slightly faster than other settings.

ONLY_EXISTING

Only apply consistency and durability guarantees if the file already exists. This may speed up file operations if the file doesn’t currently exist, but may result in a corrupted version of the new file if the system crashes while writing it.