X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=System%2FEnvironment.hs;h=f99df14bebee4327e407374d4730eef4cccbe20a;hb=be310c3938beda74ac048a0d4a29f5bc86368da1;hp=20b709f550813a3fc6b09301047f3a27317b0646;hpb=7362fdb061655b3b202e65ae1abe67adc959ddae;p=ghc-base.git

diff --git a/System/Environment.hs b/System/Environment.hs
index 20b709f..f99df14 100644
--- a/System/Environment.hs
+++ b/System/Environment.hs
@@ -48,9 +48,16 @@ getArgs =
 foreign import ccall unsafe "getProgArgv"
   getProgArgv :: Ptr CInt -> Ptr (Ptr CString) -> IO ()
 
--- Computation `getProgName' returns the name of the program
--- as it was invoked.
-
+{-|
+Computation 'getProgName' returns the name of the program as it was
+invoked.
+
+However, this is hard-to-impossible to implement on some non-Unix
+OSes, so instead, for maximum portability, we just return the leafname
+of the program as invoked. Even then there are some differences
+between platforms: on Windows, for example, a program invoked as foo
+is probably really @FOO.EXE@, and that is what 'getProgName' will return.
+-}
 getProgName :: IO String
 getProgName = 
   alloca $ \ p_argc ->