On cleanup, PSCP and PSFTP should explicitly check that the back end

is still running rather than relying on ssh_sftp_loop_iteration() to
return a bogus value.

[originally from svn r6803]

pscp.c

@@ -245,7 +245,7 @@ static int ssh_scp_recv(unsigned char *buf, int len)
     }
 
     while (outlen > 0) {
-	if (ssh_sftp_loop_iteration() < 0)
+	if (back->exitcode(backhandle) >= 0 || ssh_sftp_loop_iteration() < 0)
 	    return 0;		       /* doom */
     }