[GHC] #10957: getExecutablePath adds " (deleted)" suffix if executable was deleted under linux

[GHC]

#10957: getExecutablePath adds " (deleted)" suffix if executable was deleted under
linux
-------------------------------------+-------------------------------------
           Reporter:  aslpavel       |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Core           |           Version:  7.10.2
  Libraries                          |
           Keywords:                 |  Operating System:  Linux
       Architecture:                 |   Type of failure:  Incorrect result
  Unknown/Multiple                   |  at runtime
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 If we remove current executable or update it with a new one,
 getExecutablePath returns path with added " (deleted)" suffix. I think it
 is incorrect behavior
 , for example if you updated binary and want to exec a new one, the
 obvious way to go is to call getExecutablePath and use it. Moreover it is
 inconsistent between platforms. Problem stems from the fact the
 getExecutablePath is implemented as readlink on /proc/self/exe and it
 contains gibberish once file has been deleted.

 Example:
 {{{#!hs
 module Main (main) where

 import System.Environment (getExecutablePath)
 import System.Directory (removeFile)

 main :: IO ()
 main = do
   before <- getExecutablePath
   putStrLn $ "Before: " ++ before
   removeFile before
   after <- getExecutablePath
   putStrLn $ "After:  " ++ after
 }}}

 Output:
 {{{
 $ ./getExecutablePath
 Before: /mnt/data/Maggot/getExecutablePath
 After:  /mnt/data/Maggot/getExecutablePath (deleted)
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10957>
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