berdario / pysplice

Python CFFI wrapper around the splice syscall

Pysplice

A simple CFFI wrapper around splice(2)

splice() moves data between two file descriptors without copying between kernel address space and user address space. It transfers up to len bytes of data from the file descriptor fd_in to the file descriptor fd_out, where one of the descriptors must refer to a pipe.

API

The interesting thing is just the splice syscall itself:

• pysplice.splice(infile, off_in, outfile, off_out, size, flags=0)

  One of infile,outfile has to be a pipe. The offset of a pipe has to be None. (this is currently not checked, but it's an obvious improvement). The files have to be objects with a .fileno() method.

• pysplice.mkpipe()

  A helper function, that will return a (reader,writer) pair of objects with a .fileno() method (it just wraps os.pipe())

• pysplice.lib.SPLICE_F_MOVE

• pysplice.lib.SPLICE_F_NONBLOCK

• pysplice.lib.SPLICE_F_MORE

• pysplice.lib.SPLICE_F_GIFT