[GHC] #850: threaded RTS uses SIGALRM

[GHC]

#850: threaded RTS uses SIGALRM
----------------------------+-----------------------------------------------
 Reporter:  simonmar        |          Owner:  simonmar
     Type:  bug             |         Status:  closed  
 Priority:  normal          |      Milestone:  6.6.1   
Component:  Runtime System  |        Version:  6.4.2   
 Severity:  normal          |     Resolution:  fixed   
 Keywords:                  |     Difficulty:  Unknown 
 Testcase:                  |   Architecture:  Unknown 
       Os:  Unknown         |  
----------------------------+-----------------------------------------------
Changes (by simonmar):

  * resolution:  => fixed
  * status:  new => closed

Comment:

 The problem with `usleep()` is that it stops with `EINTR` whenever a
 signal is received, and there's no way to restart it because it doesn't
 let you know how much of the original time has expired.  The right way
 these days is to use `nanosleep()`, so I've added support for that to the
 unix package:

 {{{
 Fri Mar  2 11:41:18 GMT 2007  Simon Marlow <simonmar at microsoft.com>
   * don't retry usleep() on EINTR (see #850/#1156)

 Fri Mar  2 13:28:18 GMT 2007  Simon Marlow <simonmar at microsoft.com>
   * Provide nanosleep if we have it, and use it to implement usleep
   Fixes #1156
 }}}

 The SIGALRM question is really orthogonal: `usleep` will be interrupted by
 whatever signal we use.  However, I've modified the RTS to use
 `timer_create()` instead of `setitimer()` and therefore we now use
 `SIGVTALRM` for timer signals on both the threaded and non-threaded RTSs:

 {{{
 Fri Mar  2 03:31:04 PST 2007  Simon Marlow <simonmar at microsoft.com>
   * Use timer_create() for the interval timer, if available
 }}}

 I'll do the appropriate merging.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/850>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler