Does iOS (or iPhone OS) support file operations via SMB network shares? If so, are there any documents about how to do this?
Not sure about SMB, but I was able to read/write files on a jailbroken IPad using SFTP. OS versions 4.1, 4.2, 4.3.
On a side note, I think that the question needs a bit of clarification - what exactly are you trying to do, and whether you're working with a regular or a jailbroken device. Answers may vary greatly one knowing these things.
I thought I made it work between macbook and my iPhone simulator however it never worked for folders shared on windows machine .. please refer to a separate question I have posted - Using NSNetService class to make an SMB tcp ip connection to a folder shared on windows machine - with steps I have taken ...
I used libsmbclient from samba package for SMB operations on iOS. You can look on my project https://github.com/kolyvan/kxsmb (objective-c wrapper on libsmbclient). For now it supports a limited set of SMB operations. It mostly was designed for browsing local net and retrieving files from SMB shares.
iOS does not have any APIs to work with SMB. However, SMB is currently documented by Microsoft and implementing it is not impossible (although not easy too). I've created a freeware project which contains most of what you need to handle SMB. See
https://sourceforge.net/projects/smb4ios/
It does not use Samba or any other heavy-weight libraries. Works mostly for printers, but with what's already there it's easy to add support for file handling or whatever.
I don't care about GPL stuff, you can just reuse the code without concerns for that. Just check if the NTLM library I used has the correct license for you (or implement your own NTLM).
You may also refer to my experience, I managed to implement a SMB client for iOS : SMB/samba support on iOS?
Don't have tested yet but this might help: http://38leinad.wordpress.com/2011/03/23/windows-filesharing-library-for-ios/