title: How to read a line from a text file in c/c++?
body: <p>After exhaustive googling and visiting many forums, I am yet to find a good comprehensive answer for this question. A lot of the forums suggest using the get line 
  <code>istream&amp; getline (char* s, streamsize n )</code> function. My question is what if I don't know what the length of each line is and cannot predict what the size may be? Also what is it's equivalent in C?</p>
  
  <p>Is there any specific function in c /c++ to read one single line each time from a text file ? </p>
  
  <p>Explanation , with Code snippets will help me a lot.</p>