DFRobot FireBeetle ESP32-E Manual page 51

peek(）
Description: Read a byte from the file without advancing to the next one.
Parameter:
file: an instance of the File class
Return*: The next byte (or character), or -1 if none is available.
position( )
Description: Get the current position within the file (i.e. the location to which the next byte will be read from or written to). Syntax: file.
position()
Parameter:
file: an instance of the File class
Return*: the position within the file
print()
Description: Print data to the file, which must have been opened for writing. Syntax: file. print(data)file. print(data，BASE)
Parameter:
file: an instance of the File class
data：the data to print (char, byte, int, long, or string)
BASE(optional): the base in which to print numbers: BIN for binary (base 2), DEC for decimal (base 10), OCT for octal (base 8), HEX for
hexadecimal (base 16).
println()
Description: Print data, followed by a carriage return and newline, to the File, which must have been opened for writing. Syntax: file.
println(data)file,println(data，BASE)
Parameter:
file:an instance of the File class
data (optional): the data to print (char, byte, int, long, or string)
BASE (optional): the base in which to print numbers: BIN for binary (base 2), DEC for decimal (base 10), OCT for octal (base 8), HEX for