SD : File class
Read a byte from the file without advancing to the next one. That is, successive calls to peek() will return the same value, as will the next call to read().
peek() inherits from the Stream utility class.
file: an instance of the File class (returned by SD.open())
The next byte (or character), or -1 if none is available.
Corrections, suggestions, and new documentation should be posted to the Forum.
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