java - What happens when writing to aux file on Windows? -

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i have following code:

public class mytest {   public static void main(string [] args) throws exception {     java.io.file f = new java.io.file("aux.txt");     f.createnewfile();     java.io.filewriter fw = new java.io.filewriter(f);               fw.write("hello");     fw.flush();     fw.close();   } }

the code runs , not throw exception. except: file aux.txt not there. found f.createnewfile() return false, because aux file not allowed created on windows. ok, can live that.

but, confusion this: if filewriter did not throw exception, did write to?

according msdn

do not use following reserved names name of file: con, prn, aux, nul, com1, com2, com3, com4, com5, com6, com7, com8, com9, lpt1, lpt2, lpt3, lpt4, lpt5, lpt6, lpt7, lpt8, , lpt9. avoid these names followed extension; example, nul.txt not recommended.

false returned means, file exists. according this blog writing aux on windows causes writing auxiliary device, serial port.

in addition, try writing file called con. should appear in console.


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