html - How to make a file field that only accept pdf and doc -

i need accept pdf , doc file using input type file.

<input type="file" id="test" name="test" accept="application/msword,text/plain, application/pdf"/> 

this working in windows, in ubunthu, accept pdf file

change code this:

<input type="file" id="test" name="test" accept=".pdf,.doc"/> 

the extensions should start dot "." , separated comma ","