One common problem is to open a unique temporary file to hold
intermediate results. There are two ways to do this: the
os module and the tempfile
module. The os module has a subtle security flaw,
so it isn't recommended.
The tempfile module creates a temporary
file in the most secure and reliable manner. The
tempfile module includes an internal function,
mkstemp which dioes the hard work of creating a
unique temporary file.
-
tempfile.TemporaryFile〈
mode
〉〈
suffix
〉〈
prefix
〉〈
directory
〉
→ file
-
This function creates a file which is automatically deleted
when it is closed. All of the parameters are optional. By default,
the mode is 'w+b', allowing updating. The keyword
parameters
suffix
,
prefix
and
directory
provide some structure to the name assigned to the file. The
suffix
should include the dot, for example
suffix='.tmp'.
-
tempfile.NamedTemporaryFile〈
mode
〉〈
suffix
〉〈
prefix
〉〈
directory
〉
→ file
-
This function is similar to
TemporaryFile; it creates a file which is
automatically deleted when it is closed. The temporary file,
however, is guaranteed to be visible on the file system while the
file is open.
-
tempfile.mkstemp〈
suffix
〉〈
prefix
〉〈
directory
〉
→
fd
, file
-
This function does the essential job of creating a temporary
file. It returns a file descriptor as well as the name of the
file. The file is not automatically deleted. If necessary, the
file created by this function can be explicitly deleted with
os.remove.
import tempfile, os
fd, tempName = tempfile.mkstemp( '.d1' )
temp= open( tempName, 'w+' )
Some Processing...
This fragment will create a unique temporary file name with an
extension of .d1. Since the name is guaranteed to
be unique, this can be used without fear of damaging or overwriting any
other file.
