Some useful Unix commands

Here is a short list of useful commands that you can use from your shell (in addition to running emacs and compiling and running your program).

 

• Create a directory:

  mkdir progs
  

   

• Go to a new directory:

  cd progs/
  

  Every directory provides you access to two directories: . (the current directory) and .. (the parent directopry).

   

• View a list of all files in a directory:

  ls -lF
  

  Note that ls -F, ls -l, ls -al, ls -alF etc and even simply ls also work. Try out and find the differences. In fact, the ls takes a lot of other options.

   

• View the content of a file:

  cat filename
  

   

• Copy one file to another:

  cp file1.c file2.c
  cp file2.c mydir/file3.c
  

   

• Move a file to another:

  mv file1.c file2.c
  mv file2.c mydir/
  cd mydir/
  mv file2.c ../file1.c
  cd ../
  

   

• Delete a file:

  rm filename
  

  Note: A deleted (by rm) or overwritten (by mv) file is lost for ever. In no way you can get it back. Be very, very careful, before running these commands.