Im building a sniffer with Scapy, python 2.6.6 and windows 7 and I want to know if I can choose the interface to sniff before sniffing, kind of like Wireshark.
You can use the iface parameter.
sniff(iface="wlan0", prn=exampleFunction)
But if no interface is given, sniffing will happen on every interfaces.
You can look in the Sniffing section in the Scapy webpage