Message8096

Jython can't open files with write-only permission (write-bit is set, but read-bit is not set).

This appears to be due to org.python.core.io.FileIO using java.io.RandomAccessFile which only supports "r" or "rw" modes. The same file can be opened from Jython by using Java's java.io.FileOutputStream.


How to reproduce:

  $ touch /tmp/write-only-file
  $ chmod 200 /tmp/write-only-file
  $ jython2.7 --version
  Jython 2.7b1+
  $ jython2.7 -c 'f = open("/tmp/write-only-file", "w"); print(f)'
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
  IOError: [Errno 13] Permission denied: '/tmp/write-only-file'


Expected behavior:

  $ python -c 'f = open("/tmp/write-only-file", "w"); print(f)'
  <_io.TextIOWrapper name='/tmp/write-only-file' mode='w' encoding='ANSI_X3.4-1968'>


It seems like os.open also has the same problem:

  $ jython2.7 -c 'import os; fd = os.open("/tmp/write-only-file", os.O_WRONLY); print(fd)'
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
  IOError: [Errno 13] Permission denied: '/tmp/write-only-file'