python: open two files as one fileobject

Question

I have two files: a header and the body. I am using a library to read the whole thing. I can use "fileinput.input" to create one FileInput object and hand this to the library that reads the data. Problem is FileInput objects do not have a '.read' attribute which the library seems to expect.

I need a FileObject with a .read that is like reading both files as one.

Any ideas existing workarounds? Yes, I know I can build my own little class or cat files together. Just wondering if there is some magic FileObject joiner I've never heard of.

Answer 1

If your library reads from a file with .read(), there isn't much point in some abstraction of merging multiple file-objects as one. it is quite trivial to read everything and throw it into StringIO.

Answer 2

if you just want to call readline() on the files, try this:

def cat(*args):
    for arg in args:
        with open(arg,'r') as f:
            for line in f:
                yield line

for line in cat('/tmp/x1','/tmp/x2'):
    processLine(line)