title: Why does GCC not seem to have the filesystem standard library?
body: <p>i'm facing a problem with filesystem library, it should be included in c++17 compiler, after 2 days i tried to install gcc-7.0.2 in raspberry pi but it didn't work, it couldn't recognize the command gcc-7 or g++-7 or even <code>-std=c++17</code> so i had to install g++-6 and gcc-6 using <code>apt-get install</code>
  anyway, after installing the 6 version the compiler include c++17.
  i'm using codeblocks as IDE, i had to add a new compiler and add the option -std=c++17 to enable it,but in the main code when i include the filesystem library it says no such file or directory.</p>
  
  <p>my question is, how i can add the c++17 compiler and its library (like filesystem) correctly ??</p>