Fixes #1168

lib/system/ansi_c.nim

@@ -57,6 +57,7 @@ when not defined(SIGINT):
         SIGINT = cint(2)
         SIGSEGV = cint(11)
         SIGTERM = cint(15)
+        SIGPIPE = cint(13)
     else:
       {.error: "SIGABRT not ported to your platform".}
   else:
@@ -66,6 +67,8 @@ when not defined(SIGINT):
       SIGABRT {.importc: "SIGABRT", nodecl.}: cint
       SIGFPE {.importc: "SIGFPE", nodecl.}: cint
       SIGILL {.importc: "SIGILL", nodecl.}: cint
+    when defined(macosx) or defined(linux):
+      var SIGPIPE {.importc: "SIGPIPE", nodecl.}: cint
 
 when defined(macosx):
   when NoFakeVars:

lib/system/excpt.nim

@@ -298,7 +298,13 @@ when not defined(noSignalHandler):
       elif s == SIGILL: action("SIGILL: Illegal operation.\n")
       elif s == SIGBUS: 
         action("SIGBUS: Illegal storage access. (Attempt to read from nil?)\n")
-      else: action("unknown signal\n")
+      else:
+        block platformSpecificSignal:
+          when defined(SIGPIPE):
+            if s == SIGPIPE:
+              action("SIGPIPE: Pipe closed.\n")
+              break platformSpecificSignal
+          action("unknown signal\n")
 
     # print stack trace and quit
     when hasSomeStackTrace:
@@ -323,6 +329,8 @@ when not defined(noSignalHandler):
     c_signal(SIGFPE, signalHandler)
     c_signal(SIGILL, signalHandler)
     c_signal(SIGBUS, signalHandler)
+    when defined(SIGPIPE):
+      c_signal(SIGPIPE, signalHandler)
 
   registerSignalHandler() # call it in initialization section