C if(var & something) [duplicate]

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• Bitwise '&' operator 6 answers

Pardon for the silly question but I've been looking at an fstat() function demo and one thing keeps bugging me and I can't find an explanation for it, it's this if statement:

if(variable & something), I don't understand what the & is suppose to mean in this scenario. I've searched around and couldn't find any useful info, mainly because I don't know what exactly to search. An explanation would be much appreciated, or a redirection to one.