Reverted old FIFO functions. Still SHM enabled by default.

10 files changed, 318 insertions, 39 deletions

diff --git a/src/daemon/dlt-daemon.c b/src/daemon/dlt-daemon.c
index fb8b2e6..f2ba0cb 100755
--- a/src/daemon/dlt-daemon.c
+++ b/src/daemon/dlt-daemon.c
@@ -1004,8 +1004,15 @@ int dlt_daemon_process_client_connect(DltDaemon *daemon, DltDaemonLocal *daemon_
 
     if (daemon_local->client_connections==1)
     {
-		/* send ringbuffer done in old implementation */
-		/* nothing to do with shared memory */
+        if (daemon_local->flags.vflag)
+        {
+            dlt_log(LOG_INFO, "Send ring-buffer to client\n");
+        }
+        if (dlt_daemon_send_ringbuffer_to_client(daemon, daemon_local, verbose)==-1)
+        {
+        	dlt_log(LOG_ERR,"Can't send contents of ringbuffer to clients\n");
+			return -1;
+        }
 		
 		/* send new log state to all applications */
 		daemon->state = 1;		
@@ -1235,7 +1242,6 @@ int dlt_daemon_process_user_messages(DltDaemon *daemon, DltDaemonLocal *daemon_l
             break;
         }
         case DLT_USER_MESSAGE_LOG:
-        case DLT_USER_MESSAGE_LOG_SHM:
         {
             if (dlt_daemon_process_user_message_log(daemon, daemon_local, daemon_local->flags.vflag)==-1)
             {
@@ -1243,6 +1249,14 @@ int dlt_daemon_process_user_messages(DltDaemon *daemon, DltDaemonLocal *daemon_l
             }
             break;
         }
+        case DLT_USER_MESSAGE_LOG_SHM:
+        {
+            if (dlt_daemon_process_user_message_log_shm(daemon, daemon_local, daemon_local->flags.vflag)==-1)
+            {
+                run_loop=0;
+            }
+            break;
+        }
         case DLT_USER_MESSAGE_REGISTER_APPLICATION:
         {
             if (dlt_daemon_process_user_message_register_application(daemon, daemon_local, daemon_local->flags.vflag)==-1)
@@ -1702,6 +1716,180 @@ int dlt_daemon_process_user_message_unregister_context(DltDaemon *daemon, DltDae
 
 int dlt_daemon_process_user_message_log(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose)
 {
+    int bytes_to_be_removed;
+    int j,sent,third_value;
+    ssize_t ret;
+
+    static char text[DLT_DAEMON_TEXTSIZE];
+
+    PRINT_FUNCTION_VERBOSE(verbose);
+
+    if ((daemon==0)  || (daemon_local==0))
+    {
+    	dlt_log(LOG_ERR, "Invalid function parameters used for function dlt_daemon_process_user_message_log()\n");
+        return -1;
+    }
+
+    if (dlt_message_read(&(daemon_local->msg),(unsigned char*)daemon_local->receiver.buf+sizeof(DltUserHeader),daemon_local->receiver.bytesRcvd-sizeof(DltUserHeader),0,verbose)==0)
+    {
+        /* set overwrite ecu id */
+        if (daemon_local->flags.evalue!=0)
+        {
+            /* Set header extra parameters */
+            dlt_set_id(daemon_local->msg.headerextra.ecu, daemon->ecuid );
+            //msg.headerextra.seid = 0;
+            if (dlt_message_set_extraparameters(&(daemon_local->msg),0)==-1)
+            {
+            	dlt_log(LOG_ERR,"Can't set message extra parameters in process user message log\n");
+				return -1;
+            }
+
+            /* Correct value of timestamp, this was changed by dlt_message_set_extraparameters() */
+            daemon_local->msg.headerextra.tmsp = DLT_BETOH_32(daemon_local->msg.headerextra.tmsp);
+        }
+
+        /* prepare storage header */
+        if (DLT_IS_HTYP_WEID(daemon_local->msg.standardheader->htyp))
+        {
+            if (dlt_set_storageheader(daemon_local->msg.storageheader,daemon_local->msg.headerextra.ecu)==-1)
+            {
+				dlt_log(LOG_ERR,"Can't set storage header in process user message log\n");
+				return -1;
+            }
+        }
+        else
+        {
+            if (dlt_set_storageheader(daemon_local->msg.storageheader,daemon->ecuid)==-1)
+            {
+				dlt_log(LOG_ERR,"Can't set storage header in process user message log\n");
+				return -1;
+            }
+        }
+
+        {
+            /* if no filter set or filter is matching display message */
+            if (daemon_local->flags.xflag)
+            {
+                if (dlt_message_print_hex(&(daemon_local->msg),text,DLT_DAEMON_TEXTSIZE,verbose)==-1)
+				{
+					dlt_log(LOG_ERR,"dlt_message_print_hex() failed!\n");
+				}
+            } /*  if */
+            else if (daemon_local->flags.aflag)
+            {
+                if (dlt_message_print_ascii(&(daemon_local->msg),text,DLT_DAEMON_TEXTSIZE,verbose)==-1)
+                {
+					dlt_log(LOG_ERR,"dlt_message_print_ascii() failed!\n");
+				}
+            } /* if */
+            else if (daemon_local->flags.sflag)
+            {
+                if (dlt_message_print_header(&(daemon_local->msg),text,DLT_DAEMON_TEXTSIZE,verbose)==-1)
+				{
+					dlt_log(LOG_ERR,"dlt_message_print_header() failed!\n");
+				}
+                /* print message header only */
+            } /* if */
+
+            sent=0;
+
+			/* write message to offline trace */
+			if(((daemon->mode == DLT_USER_MODE_INTERNAL) || (daemon->mode == DLT_USER_MODE_BOTH)) && daemon_local->flags.offlineTraceDirectory[0])
+			{
+				dlt_offline_trace_write(&(daemon_local->offlineTrace),daemon_local->msg.headerbuffer,daemon_local->msg.headersize,
+										daemon_local->msg.databuffer,daemon_local->msg.datasize,0,0);
+				sent = 1;
+			}
+
+            /* look if TCP connection to client is available */
+            for (j = 0;((daemon->mode == DLT_USER_MODE_EXTERNAL) || (daemon->mode == DLT_USER_MODE_BOTH)) &&  (j <= daemon_local->fdmax); j++)
+            {
+                /* send to everyone! */
+                if (FD_ISSET(j, &(daemon_local->master)))
+                {
+                    /* except the listener and ourselves */
+                    if (daemon_local->flags.yvalue[0])
+                    {
+                        third_value = daemon_local->fdserial;
+                    }
+                    else
+                    {
+                        third_value = daemon_local->sock;
+                    }
+
+                    if ((j != daemon_local->fp) && (j != daemon_local->sock) && (j != third_value))
+                    {
+                        DLT_DAEMON_SEM_LOCK();
+
+                        if (daemon_local->flags.lflag)
+                        {
+                            send(j,dltSerialHeader,sizeof(dltSerialHeader),0);
+                        }
+
+                        send(j,daemon_local->msg.headerbuffer+sizeof(DltStorageHeader),daemon_local->msg.headersize-sizeof(DltStorageHeader),0);
+                        send(j,daemon_local->msg.databuffer,daemon_local->msg.datasize,0);
+
+                        DLT_DAEMON_SEM_FREE();
+
+                        sent=1;
+                    } /* if */
+                    else if ((j == daemon_local->fdserial) && (daemon_local->flags.yvalue!=0))
+                    {
+                        DLT_DAEMON_SEM_LOCK();
+
+                        if (daemon_local->flags.lflag)
+                        {
+                            ret=write(j,dltSerialHeader,sizeof(dltSerialHeader));
+                        }
+
+                        ret=write(j,daemon_local->msg.headerbuffer+sizeof(DltStorageHeader),daemon_local->msg.headersize-sizeof(DltStorageHeader));
+                        ret=write(j,daemon_local->msg.databuffer,daemon_local->msg.datasize);
+
+                        DLT_DAEMON_SEM_FREE();
+
+                        sent=1;
+                    }
+                } /* if */
+            } /* for */
+
+            /* Message was not sent to client, so store it in client ringbuffer */
+            if (sent==0)
+            {
+                if (dlt_ringbuffer_put3(&(daemon->client_ringbuffer),
+                                    daemon_local->msg.headerbuffer+sizeof(DltStorageHeader),daemon_local->msg.headersize-sizeof(DltStorageHeader),
+                                    daemon_local->msg.databuffer,daemon_local->msg.datasize,
+                                    0, 0
+                                   )<0)
+				{
+					dlt_log(LOG_ERR,"Storage of message in history buffer failed! Message discarded.\n");
+				}
+            }
+
+        }
+        /* keep not read data in buffer */
+        bytes_to_be_removed = daemon_local->msg.headersize+daemon_local->msg.datasize-sizeof(DltStorageHeader)+sizeof(DltUserHeader);
+        if (daemon_local->msg.found_serialheader)
+        {
+            bytes_to_be_removed += sizeof(dltSerialHeader);
+        }
+
+        if (dlt_receiver_remove(&(daemon_local->receiver),bytes_to_be_removed)==-1)
+        {
+        	dlt_log(LOG_ERR,"Can't remove bytes from receiver\n");
+        	return -1;
+        }
+    }
+    else
+    {
+    	dlt_log(LOG_ERR,"Can't read messages from receiver\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+int dlt_daemon_process_user_message_log_shm(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose)
+{
     int bytes_to_be_removed=0;
     int j,sent,third_value;
     ssize_t ret;
@@ -1724,29 +1912,18 @@ int dlt_daemon_process_user_message_log(DltDaemon *daemon, DltDaemonLocal *daemo
 	//dlt_shm_status(&(daemon_local->dlt_shm));
 	while (1)
     {		
-		if(userheader->message == DLT_USER_MESSAGE_LOG_SHM) {
-			/* log message in SHM */
-			if((size = dlt_shm_copy(&(daemon_local->dlt_shm),rcv_buffer,10000)) <= 0)
-				break;
-			if (dlt_message_read(&(daemon_local->msg),rcv_buffer,size,0,verbose)!=0) {
-				break;
-				dlt_log(LOG_ERR,"Can't read messages from shm\n");
-				return -1;
-			}				
-			bytes_to_be_removed = daemon_local->msg.headersize+daemon_local->msg.datasize-sizeof(DltStorageHeader)+sizeof(DltUserHeader);
-			if (daemon_local->msg.found_serialheader)
-			{
-				bytes_to_be_removed += sizeof(dltSerialHeader);
-			}
-   		}
-		else  { /* userheader->message == DLT_USER_MESSAGE_LOG */
-			/* log message in FIFO */
-			if(dlt_message_read(&(daemon_local->msg),(unsigned char*)daemon_local->receiver.buf+sizeof(DltUserHeader),daemon_local->receiver.bytesRcvd-sizeof(DltUserHeader),0,verbose)!=0) {
-				break;
-				dlt_log(LOG_ERR,"Can't read messages from receiver\n");
-				return -1;
-			}				;
-			bytes_to_be_removed = sizeof(DltUserHeader);
+		/* log message in SHM */
+		if((size = dlt_shm_copy(&(daemon_local->dlt_shm),rcv_buffer,10000)) <= 0)
+			break;
+		if (dlt_message_read(&(daemon_local->msg),rcv_buffer,size,0,verbose)!=0) {
+			break;
+			dlt_log(LOG_ERR,"Can't read messages from shm\n");
+			return -1;
+		}				
+		bytes_to_be_removed = daemon_local->msg.headersize+daemon_local->msg.datasize-sizeof(DltStorageHeader)+sizeof(DltUserHeader);
+		if (daemon_local->msg.found_serialheader)
+		{
+			bytes_to_be_removed += sizeof(dltSerialHeader);
 		}
 		
 		/* set overwrite ecu id */
@@ -1827,7 +2004,7 @@ int dlt_daemon_process_user_message_log(DltDaemon *daemon, DltDaemonLocal *daemo
 			if (FD_ISSET(j, &(daemon_local->master)))
 			{
 				/* except the listener and ourselves */
-				if (daemon_local->flags.yvalue!=0)
+				if (daemon_local->flags.yvalue[0])
 				{
 					third_value = daemon_local->fdserial;
 				}
@@ -2003,6 +2180,72 @@ int dlt_daemon_process_user_message_log_mode(DltDaemon *daemon, DltDaemonLocal *
     return 0;
 }
 
+int dlt_daemon_send_ringbuffer_to_client(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose)
+{
+    static uint8_t data[DLT_DAEMON_RINGBUFFER_SIZE];
+    size_t length=0;
+    int j, third_value;
+    ssize_t ret;
+
+    PRINT_FUNCTION_VERBOSE(verbose);
+
+    if ((daemon==0)  || (daemon_local==0))
+    {
+    	dlt_log(LOG_ERR, "Invalid function parameters used for function dlt_daemon_send_ringbuffer_to_client()\n");
+        return -1;
+    }
+
+	/* Attention: If the message can't be send at this time, it will be silently discarded. */
+    while ((dlt_ringbuffer_get(&(daemon->client_ringbuffer), data, &length ))!=-1)
+    {
+        /* look if TCP connection to client is available */
+        for (j = 0; j <= daemon_local->fdmax; j++)
+        {
+            /* send to everyone! */
+            if (FD_ISSET(j, &(daemon_local->master)))
+            {
+                /* except the listener and ourselves */
+                if (daemon_local->flags.yvalue[0])
+                {
+                    third_value = daemon_local->fdserial;
+                }
+                else
+                {
+                    third_value = daemon_local->sock;
+                }
+
+                if ((j != daemon_local->fp) && (j != daemon_local->sock) && (j != third_value))
+                {
+                    DLT_DAEMON_SEM_LOCK();
+
+                    if (daemon_local->flags.lflag)
+                    {
+                        send(j,dltSerialHeader,sizeof(dltSerialHeader),0);
+                    }
+                    send(j,data,length,0);
+
+                    DLT_DAEMON_SEM_FREE();
+
+                } /* if */
+                else if ((j == daemon_local->fdserial) && (daemon_local->flags.yvalue[0]))
+                {
+                    DLT_DAEMON_SEM_LOCK();
+
+                    if (daemon_local->flags.lflag)
+                    {
+                        ret=write(j,dltSerialHeader,sizeof(dltSerialHeader));
+                    }
+                    ret=write(j,data,length);
+
+                    DLT_DAEMON_SEM_LOCK();
+                }
+            } /* if */
+        } /* for */
+    }
+
+    return 0;
+}
+
 void dlt_daemon_timingpacket_thread(void *ptr)
 {
     DltDaemonPeriodicData info;
diff --git a/src/daemon/dlt-daemon.h b/src/daemon/dlt-daemon.h
index bc3ba39..5d15326 100755
--- a/src/daemon/dlt-daemon.h
+++ b/src/daemon/dlt-daemon.h
@@ -171,9 +171,11 @@ int dlt_daemon_process_user_message_unregister_application(DltDaemon *daemon, Dl
 int dlt_daemon_process_user_message_register_context(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

 int dlt_daemon_process_user_message_unregister_context(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

 int dlt_daemon_process_user_message_log(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

+int dlt_daemon_process_user_message_log_shm(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

 int dlt_daemon_process_user_message_set_app_ll_ts(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

 int dlt_daemon_process_user_message_log_mode(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

 

+int dlt_daemon_send_ringbuffer_to_client(DltDaemon *daemon, DltDaemonLocal *daemon_local, int verbose);

 void dlt_daemon_timingpacket_thread(void *ptr);

 int dlt_daemon_make_periodic (unsigned int period, DltDaemonPeriodicData *info, int verbose);

 void dlt_daemon_wait_period(DltDaemonPeriodicData *info, int verbose);

diff --git a/src/daemon/dlt.conf b/src/daemon/dlt.conf
index a410d19..380e0bc 100644
--- a/src/daemon/dlt.conf
+++ b/src/daemon/dlt.conf
@@ -16,16 +16,16 @@
 # SendSerialHeader = 1
 
 # Send automatic get log info response during context registration
-# SendContextRegistration = 1
+SendContextRegistration = 1
 
 # Send automatic time packets every second if client is connected (Default: 0)
-# SendMessageTime = 1
+SendMessageTime = 1
 
 # Set ECU ID (Default: ECU1)
 ECUId = ENAT
 
 # Size of shared memory (Default: 100000)
-SharedMemorySize = 40000
+SharedMemorySize = 4000000
 
 # Directory where to store the persistant configuration (Default: /tmp)
 # PersistanceStoragePath = /tmp
diff --git a/src/daemon/dlt_daemon_common.c b/src/daemon/dlt_daemon_common.c
index 4877825..aaed7a2 100755
--- a/src/daemon/dlt_daemon_common.c
+++ b/src/daemon/dlt_daemon_common.c
@@ -187,6 +187,12 @@ int dlt_daemon_init(DltDaemon *daemon,const char *runtime_directory, int verbose
 
     dlt_set_id(daemon->ecuid,"");
 
+    /* initialize ring buffer for client connection */
+    if (dlt_ringbuffer_init(&(daemon->client_ringbuffer), DLT_DAEMON_RINGBUFFER_SIZE)==-1)
+    {
+    	return -1;
+    }
+
     return 0;
 }
 
@@ -2138,8 +2144,16 @@ void dlt_daemon_control_send_control_message( int sock, DltDaemon *daemon, DltMe
     }
     else
     {
-		/* message can not be sent */
-		/* in old implementation control message was stored in buffer */
+        /* Store message in history buffer */
+        if (dlt_ringbuffer_put3(&(daemon->client_ringbuffer),
+                            msg->headerbuffer+sizeof(DltStorageHeader),msg->headersize-sizeof(DltStorageHeader),
+                            msg->databuffer,msg->datasize,
+                            0, 0
+                           )<0)
+		{
+			dlt_log(LOG_ERR,"Storage of message in history buffer failed! Message discarded.\n");
+			return;
+		}
     }
 }
 
diff --git a/src/daemon/dlt_daemon_common.h b/src/daemon/dlt_daemon_common.h
index 2bdb637..17bc32f 100755
--- a/src/daemon/dlt_daemon_common.h
+++ b/src/daemon/dlt_daemon_common.h
@@ -149,6 +149,7 @@ typedef struct
 	char ecuid[DLT_ID_SIZE];       /**< ECU ID of daemon */

 	int sendserialheader;          /**< 1: send serial header; 0 don't send serial header */

 	int timingpackets;              /**< 1: send continous timing packets; 0 don't send continous timing packets */

+	DltRingBuffer client_ringbuffer; /**< Ring-buffer for storing received logs while no client connection is available */

 	char runtime_application_cfg[256]; /**< Path and filename of persistent application configuration */

 	char runtime_context_cfg[256]; /**< Path and filename of persistent context configuration */

 	char runtime_configuration[256]; /**< Path and filename of persistent configuration */

diff --git a/src/lib/dlt_filetransfer.c b/src/lib/dlt_filetransfer.c
index 935573d..7377cb6 100644
--- a/src/lib/dlt_filetransfer.c
+++ b/src/lib/dlt_filetransfer.c
@@ -350,7 +350,7 @@ int dlt_user_log_file_data(DltContext *fileContext,const char *filename, int pac
 					DLT_STRING("FLDA")	
 				);
 				
-				doTimeout(timeout);
+				//doTimeout(timeout);
 					
 		} else {
 			pkgNumber = 0;
@@ -367,7 +367,7 @@ int dlt_user_log_file_data(DltContext *fileContext,const char *filename, int pac
 					DLT_STRING("FLDA")		
 				);
 				
-				doTimeout(timeout); 
+				//doTimeout(timeout); 
 			}
 		}
 		
diff --git a/src/lib/dlt_user.c b/src/lib/dlt_user.c
index bdb9efe..eac0215 100755
--- a/src/lib/dlt_user.c
+++ b/src/lib/dlt_user.c
@@ -2048,7 +2048,11 @@ int dlt_user_log_send_log(DltContextData *log, int mtype)
     }
 
     /* also for Trace messages */
+#ifdef DLT_SHM_ENABLE
     if (dlt_user_set_userheader(&userheader, DLT_USER_MESSAGE_LOG_SHM)==-1)
+#else
+    if (dlt_user_set_userheader(&userheader, DLT_USER_MESSAGE_LOG)==-1)
+#endif
     {
 		return -1;
     }
@@ -2182,6 +2186,7 @@ int dlt_user_log_send_log(DltContextData *log, int mtype)
             }
         }
 
+#ifdef DLT_SHM_ENABLE
 		dlt_shm_push(&dlt_user.dlt_shm,msg.headerbuffer+sizeof(DltStorageHeader), msg.headersize-sizeof(DltStorageHeader),
 									log->buffer, log->size,0,0);                   
 
@@ -2190,7 +2195,14 @@ int dlt_user_log_send_log(DltContextData *log, int mtype)
                                 &(userheader), sizeof(DltUserHeader),
                                 0, 0,
                                 0, 0);
-        		
+#else
+        /* log to FIFO */
+        ret = dlt_user_log_out3(dlt_user.dlt_log_handle,
+                                &(userheader), sizeof(DltUserHeader),
+                                msg.headerbuffer+sizeof(DltStorageHeader), msg.headersize-sizeof(DltStorageHeader),
+                                log->buffer, log->size);
+
+#endif        		
         /* store message in ringbuffer, if an error has occured */
         if (ret!=DLT_RETURN_OK)
         {
@@ -2830,12 +2842,17 @@ void dlt_user_log_reattach_to_daemon(void)
 
                     if (size>0)
                     {
+#ifdef DLT_SHM_ENABLE						
 						dlt_shm_push(&dlt_user.dlt_shm,buf+sizeof(DltUserHeader),size-sizeof(DltUserHeader),0,0,0,0);                   
 
                         /* log to FIFO */
                         ret = dlt_user_log_out3(dlt_user.dlt_log_handle, buf,sizeof(DltUserHeader),0,0,0,0);
+#else
+                        /* log to FIFO */
+                        ret = dlt_user_log_out3(dlt_user.dlt_log_handle, buf,size,0,0,0,0);
+#endif
 
-                        /* in case of error, push message back to ringbuffer */
+                        /* in case of error, push message back to ringbuffer */                        
                         if (ret!=DLT_RETURN_OK)
                         {
                             DLT_SEM_LOCK();
diff --git a/src/system/dlt-system-log.c b/src/system/dlt-system-log.c
index cf2b495..6a76221 100644
--- a/src/system/dlt-system-log.c
+++ b/src/system/dlt-system-log.c
@@ -181,9 +181,11 @@ void dlt_system_filetransfer_run(DltSystemOptions *options,DltSystemRuntime *run
 				printf("Error: dlt_user_log_file_data\n");
 				return;
 			}			
+#ifdef DLT_SHM_ENABLE
 			/* wait sending next package if more than 50% of buffer used */
 			dlt_user_check_buffer(&total_size, &used_size);
 			if((total_size - used_size) < (total_size/2))
+#endif
 				break;
 		}
 		if(runtime->filetransferLastSentPackage==runtime->filetransferCountPackages) {
diff --git a/src/system/dlt-system.c b/src/system/dlt-system.c
index 2040aab..c2df24c 100755
--- a/src/system/dlt-system.c
+++ b/src/system/dlt-system.c
@@ -630,7 +630,7 @@ int main(int argc, char* argv[])
 	    /* Wait up to one second. */
 		tv.tv_sec = 0;
 		if(runtime.filetransferRunning)
-			tv.tv_usec = 10000;
+			tv.tv_usec = 20000;
 		else
 			tv.tv_usec = (dlt_uptime()-lasttime+10000)*100;
 
diff --git a/src/system/dlt-system.conf b/src/system/dlt-system.conf
index 1811fc3..235f00e 100644
--- a/src/system/dlt-system.conf
+++ b/src/system/dlt-system.conf
@@ -38,11 +38,11 @@ FiletransferContextId = FILE
 
 # Time after startup of dlt-system when first file is transfered (Default: 30)
 # Time in seconds
-FiletransferTimeStartup = 30
+FiletransferTimeStartup = 10
 
 # Time to wait when transfered file is deleted and next file transfer starts (Default: 10)
 # Time in seconds
-FiletransferTimeDelay = 10
+FiletransferTimeDelay = 3
 
 ########################################################################
 # Log short files, expecially from proc filesystem