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Created by Daneel S. Yaitskov@yaitskovDeveloper

getExecutablePath returns ld loader path

if Haskell program is launched through ld linkder then System.Environment.getExecutablePath returns path to the linker not to the program, meanwhile getArgs works correctly and first argument is not a path to the Haskell program, the last fact makes hard to implement workaround.

module Main where
import System.Environment
main :: IO ()
main = do
  p <- getExecutablePath
  print p
  x <- getArgs
  print x
ghc --make -o print-args Main.hs 
readelf -a print-args | grep Requesting
      [Requesting program interpreter: /lib64/ld-linux-x86-64.so.2]
/lib64/ld-linux-x86-64.so.2 $PWD/print-args a b c
"/usr/lib/x86_64-linux-gnu/ld-2.28.so"
["a","b","c"]
ghc --version
The Glorious Glasgow Haskell Compilation System, version 8.10.4

uname -a
Linux diehard 5.9.13 #1 SMP Wed Dec 9 14:12:51 MSK 2020 x86_64 GNU/Linux

workaround:

getFullProgName :: IO String
getFullProgName =
  alloca $ \ p_argc ->
  alloca $ \ p_argv -> do
   getFullProgArgv p_argc p_argv
   peek p_argv >>= peek >>= peekCString

foreign import ccall unsafe "getFullProgArgv"
    getFullProgArgv :: Ptr CInt -> Ptr (Ptr CString) -> IO ()

main = getFullProgName >>= putStrLn
Edited by Daneel S. Yaitskov