getTmpDir
Gets the directory to use for temporary files.
On UNIX, this is taken from the TMPDIR
environment variable. If the variable is not set, P_tmpdir
is used, as defined by the system C library. Failing that, a hard-coded default of "/tmp" is returned.
On Windows, the TEMP
environment variable is used, with the root directory of the Windows installation (eg: "C:\") used as a default.
The encoding of the returned string is system-defined. On Windows, it is always UTF-8. The return value is never null or the empty string.
Return
the directory to use for temporary files.