parseInt() returns the first valid (long) integer number from the current position. Initial characters that are not integers (or the minus sign) are skipped.

In particular:

  • Initial characters that are not digits or a minus sign, are skipped;
  • Parsing stops when no characters have been read for a configurable time-out value, or a non-digit is read;
  • If no valid digits were read when the time-out (see Stream.setTimeout()) occurs, 0 is returned;

This function is part of the Stream class, and can be called by any class that inherits from it (Wire, Serial, etc). See the Stream class main page for more information.



stream.parseInt(''list', char skipchar')


  • stream : an instance of a class that inherits from Stream.
  • list : the stream to check for ints (char)
  • skipChar: used to skip the indicated char in the search. Used for example to skip thousands divider.


  • long


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