diff --git a/library/DFProcess-linux-SHM.cpp b/library/DFProcess-linux-SHM.cpp
index f8a83275d..c1f8b954a 100644
--- a/library/DFProcess-linux-SHM.cpp
+++ b/library/DFProcess-linux-SHM.cpp
@@ -215,6 +215,7 @@ void SHMProcess::Private::FreeLocks()
     {
         close(suspend_lock);
         locked = false;
+        suspended = false;
         suspend_lock = -1;
     }
 }
@@ -327,8 +328,9 @@ SHMProcess::SHMProcess(uint32_t PID, vector< memory_info* >& known_versions)
     }
     if(!bridgeOK)
     {
-        detach();
         throw Error::SHMVersionMismatch();
+        detach();
+        
         return;
     }
     
@@ -473,11 +475,13 @@ bool SHMProcess::suspend()
     if(D_SHMCMD == CORE_RUN)
     {
         //fprintf(stderr,"%d invokes step\n",d->attachmentIdx);
+        // wait for the next window
         D_SHMCMD = CORE_STEP;
     }
     else
     {
         //fprintf(stderr,"%d invokes suspend\n",d->attachmentIdx);
+        // lock now
         D_SHMCMD = CORE_SUSPEND;
     }
     //fprintf(stderr,"waiting for lock\n");
@@ -579,24 +583,22 @@ bool SHMProcess::attach()
     /*
     * Attach the segment
     */
-    if ((d->shm_addr = (char *) shmat(d->shm_ID, NULL, 0)) != (char *) -1)
+    if ((d->shm_addr = (char *) shmat(d->shm_ID, NULL, 0)) == (char *) -1)
+    {
+        d->FreeLocks();
+        cerr << "can't attach segment" << endl;
+        return false;
+    }
+    d->attached = true;
+    if(!suspend())
     {
-        d->attached = true;
-        if(suspend())
-        {
-            d->suspended = true;
-            g_pProcess = this;
-            return true;
-        }
-        d->attached = false;
-        cerr << "unable to suspend" << endl;
         shmdt(d->shm_addr);
         d->FreeLocks();
+        cerr << "unable to suspend" << endl;
         return false;
     }
-    cerr << "unable to attach" << endl;
-    d->FreeLocks();
-    return false;
+    g_pProcess = this;
+    return true;
 }
 
 bool SHMProcess::detach()
diff --git a/shmserver/mod-core.cpp b/shmserver/mod-core.cpp
index 7b5f0a1ab..3bc27b12e 100644
--- a/shmserver/mod-core.cpp
+++ b/shmserver/mod-core.cpp
@@ -51,7 +51,7 @@ bool useYield = 0;
 int currentClient = -1;
 
 #define SHMHDR ((shm_core_hdr *)shm)
-#define SHMCMDPP ((shm_core_hdr *) shm)->cmd[currentClient].pingpong
+#define SHMCMD ((uint32_t *)shm )[currentClient]
 #define SHMDATA(type) ((type *)(shm + SHM_HEADER))
 
 void ReadRaw (void * data)
@@ -264,7 +264,7 @@ void SHM_Act (void)
             else
             {
                 full_barrier
-                SHMCMDPP = CORE_RUNNING;
+                SHMCMD = CORE_RUNNING;
                 fprintf(stderr,"dfhack: Broke out of loop, other process disappeared.\n");
             }
         }
@@ -276,7 +276,7 @@ void SHM_Act (void)
         // this is very important! copying two words separately from the command variable leads to inconsistency.
         // Always copy the thing in one go.
         // Also, this whole SHM thing probably only works on intel processors
-        atomic  = *(uint32_t *) (shm + 4*currentClient); //SHMHDR->cmd[currentClient];
+        atomic  = SHMCMD;
         full_barrier
         
         DFPP_module & mod = module_registry[ ((shm_cmd)atomic).parts.module ];
@@ -303,7 +303,7 @@ void SHM_Act (void)
                     currentClient,((shm_cmd)atomic).parts.module,((shm_cmd)atomic).parts.command, cmd._function);
             fprintf(stderr, "%s\n",cmd.name.c_str());
             // FIXME: WHAT HAPPENS WHEN A 'NEXTSTATE' IS FROM A DIFFERENT MODULE THAN 'CORE'? Yeah. It doesn't work.
-            SHMCMDPP = cmd.nextState;
+            SHMCMD = cmd.nextState;
             fprintf(stderr, "Server set %d\n",cmd.nextState);
         }
         full_barrier
diff --git a/shmserver/shms-linux.cpp b/shmserver/shms-linux.cpp
index 3e79753bf..aa157c1be 100644
--- a/shmserver/shms-linux.cpp
+++ b/shmserver/shms-linux.cpp
@@ -196,7 +196,7 @@ void SHM_Init ( void )
     // make sure we don't stall or do crazy stuff
     for(int i = 0; i < SHM_MAX_CLIENTS;i++)
     {
-        ((shm_cmd *)shm)[i].pingpong = CORE_RUNNING;
+        ((uint32_t *)shm)[i] = CORE_RUNNING;
     }
     InitModules();
 }