head utility works

head.nim

@@ -1,10 +1,18 @@
 import cligen, os, streams
 import common
 
-proc main(files:seq[string]) =
+proc main(files:seq[string], lines=10, bytes=0) =
     for file in files:
         var s = newFileStream(file, fmRead)
-        while not s.atEnd:
+        if bytes > 0:
+            var currentByte = 0
+            while not s.atEnd and currentByte < bytes:
                 write(stdout, s.readChar)
+                inc currentByte
+        elif lines > 0:
+            var currentLine = 0
+            while not s.atEnd and currentLine < lines:
+                echo s.readLine
+                inc currentLine
 
 dispatch(main, version=("version", nimbaseVersion))