Name: asR10013 Date: 11/21/2000



    The following sample code and output show incorrect behavior of
method java.io.File.createNewFile under Solaris.
    API specificaion reads:

public boolean createNewFile() throws IOException

    Atomically creates a new, empty file named by this abstract pathname if
    and only if a file with this name does not yet exist. The check for the
    existence of the file and the creation of the file if it does not exist are a
    single operation that is atomic with respect to all other filesystem activities
    that might affect the file. This method, in combination with the
    deleteOnExit() method, can therefore serve as the basis for a simple but
    reliable cooperative file-locking protocol.
    Returns:
true if the named file does not exist and was successfully created;
false if the named file already exists
    Throws:
IOException - If an I/O error occurred
SecurityException - If a security manager exists and its
SecurityManager.checkWrite(java.io.FileDescriptor) method
denies write access to the file
---------------------- end of citation -------------------------------

    There is a difference in behavior between linux and solaris jvms.
Solaris jdk1.3.1-b08 incorrectly throws IOException for filename '/'
whereas this file exists and method should return false.
    The problem is reproducible on:
         * solaris jdk1.3.1-b08
* solaris jdk1.4.0-b40

    JCK1.3a test api/java_io/File/OtherMethodsTests.html#createNewFile
gives incorrect result, because of this bug.
------------------------ test.java -----------------------------------
import java.io.*;

class test {

    public static void main(String args[]) {
File f[] = { new File(""), new File("/"), new File("/tmp") };

for (int i=0; i<f.length; i++) {
System.out.println("Checking filename '"+(f[i]).getPath()+"'");
try {
System.out.println("result: "+(f[i]).createNewFile());
} catch (IOException e) {
System.out.println(e);
}
}
    }
}
---------------------- linux output ----------------------------------
$ java -version
java version "1.3.1beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1beta-b08)
Java HotSpot(TM) Client VM (build 1.3.1beta-b08, mixed mode)
$ java test
Checking filename ''
java.io.IOException: No such file or directory
Checking filename '/'
result: false
Checking filename '/tmp'
result: false
--------------------- solaris output ---------------------------------
$ java -version
java version "1.3.1beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1beta-b08)
Java HotSpot(TM) Client VM (build 1.3.1beta-b08, mixed mode)
$ java test
Checking filename ''
java.io.IOException: No such file or directory
Checking filename '/'
java.io.IOException: Invalid argument
Checking filename '/tmp'
result: false
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