SPIFFS File implementation of seek is non-standard for Arduino

[Makuna]

Basic Infos

SPIFFS File implementation of seek is non-standard for Arduino

Description

All implementations of "seek" for Arduino File objects only take one param and assume seek from the front of the file.
The SPIFFs only implements one "seek" that requires a second param that defines the SeekMode. This makes it difficult to write code/libraries that will work across SD file objects and SPIFFs file objects.

The solution is change the SeekMode to have a default value of SeekSet or add another seek that doesn't take the second parameter.

FS.h

bool seek(uint32_t pos, SeekMode mode = SeekSet);

or

bool seek(uint32_t pos)
{
    seek(pos, SeekSet);
}

[Makuna]

ALSO, the read method was changed. While agree with returning size_t, the change of the first param from void* to uint8_t* could be problematic; but is easily worked around by always casting to uint8_t* when passing anything that is not already a collection of 8bit types (like a structure).

[devyte]

Referenced PR is already merged, closing.