If a File Extension Is Not in the File Name?

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If a file extension is not in the file name, and not because it is hidden, such as a .pdf, how do you determine its file type?

Some file formats have a hint at the beginning (PDF Files start with a string like '%PDF-1.3') but many file formats don't really have a good visual indication of what the content of the file is. If you are lucky, your file will have a magic number indicating what type of file it is. You can trudge through that and see if you can find your answer. http.//en.wikipedia.org/wiki/Magic_number_(programming) If you are lucky enough to have a text file on your hands, you can open it with your trusty notepad like application and examine the contents. Hopefully you will get some hint as to what the file is supposed to be. Many text based Unix-like files have a shebang at the start of the file indicating what program is used to interpret the file. This looks something like '#!/bin/sh'. (This is a magic number too!) If you are faced with an unknown binary blob that doesn't give any clue to the nature of its contents, unfortunately, trial and error is your only route. If your operating system is simply hiding the extension then User-13375181939089766119's answer is sufficient.

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Type on PDF: All You Need to Know

If your operating system allows for file extension to be removed from the file name, it's time to call someone and find out how to reverse engineer that too. If your operating system won't let you run your own program to analyze the contents of an unknown blob for you, I recommend installing an application to run that special binary, and doing this after it's dumped to disk If you have not already done so, please remember to update our blog regularly, and also do subscribe to us on Twitter hackthissite. You don't necessarily need this if you can already tell the exact type of file. Many other file systems have an identification of their own. So, the best way to get this information is to search. If this is your first time trying a new file system, I suggest you test it with something you have already done in the past As.