diff -r c7e9b5edb8d4 src/9vx/Makefrag
--- a/src/9vx/Makefrag	Sun Dec 27 09:49:22 2009 -0800
+++ b/src/9vx/Makefrag	Tue Mar 16 21:29:23 2010 -0700
@@ -74,6 +74,7 @@
 		devmnt.o \
 		devproc.o \
 		devpipe.o \
+		devram.o \
 		devroot.o \
 		devsd.o \
 		devsrv.o \
diff -r c7e9b5edb8d4 src/9vx/a/AUTOGEN
--- a/src/9vx/a/AUTOGEN	Sun Dec 27 09:49:22 2009 -0800
+++ b/src/9vx/a/AUTOGEN	Tue Mar 16 21:29:23 2010 -0700
@@ -38,6 +38,7 @@
 /sys/src/9/port/devmnt.c
 /sys/src/9/port/devpipe.c
 /sys/src/9/port/devproc.c
+/sys/src/9/port/devram.c
 /sys/src/9/port/devroot.c
 /sys/src/9/port/devsrv.c
 /sys/src/9/port/devtls.c
diff -r c7e9b5edb8d4 src/9vx/a/devproc.c
--- a/src/9vx/a/devproc.c	Sun Dec 27 09:49:22 2009 -0800
+++ b/src/9vx/a/devproc.c	Tue Mar 16 21:29:23 2010 -0700
@@ -31,6 +31,7 @@
 	Qtext,
 	Qwait,
 	Qprofile,
+	Qtruss,
 };
 
 enum
@@ -84,6 +85,7 @@
 	"text",		{Qtext},	0,			0000,
 	"wait",		{Qwait},	0,			0400,
 	"profile",	{Qprofile},	0,			0400,
+	"truss",	{Qtruss},	0,			0400,
 };
 
 static
@@ -397,6 +399,7 @@
 	case Qwait:
 	case Qregs:
 	case Qfpregs:
+	case Qtruss:
 		nonone(p);
 		break;
 
@@ -706,6 +709,12 @@
 		memmove(a, &up->genbuf[offset], n);
 		return n;
 
+	case Qtruss:
+		if (! p->syscalltrace)
+			return 0;
+		n = readstr(offset, a, n, p->syscalltrace);
+		return n;
+
 	case Qmem:
 		if(offset < USTKTOP)
 			return procctlmemio(p, offset, n, va, 1);
diff -r c7e9b5edb8d4 src/9vx/a/portdat.h
--- a/src/9vx/a/portdat.h	Sun Dec 27 09:49:22 2009 -0800
+++ b/src/9vx/a/portdat.h	Tue Mar 16 21:29:23 2010 -0700
@@ -752,6 +752,9 @@
 	 *  machine specific MMU
 	 */
 	PMMU pmmu;
+	/* syscall trace */
+	char *syscalltrace;
+	
 };
 
 enum
diff -r c7e9b5edb8d4 src/9vx/devtab.c
--- a/src/9vx/devtab.c	Sun Dec 27 09:49:22 2009 -0800
+++ b/src/9vx/devtab.c	Tue Mar 16 21:29:23 2010 -0700
@@ -8,6 +8,7 @@
 extern Dev consdevtab;
 extern Dev rootdevtab;
 extern Dev pipedevtab;
+extern Dev ramdevtab;
 extern Dev ssldevtab;
 extern Dev tlsdevtab;
 extern Dev mousedevtab;
@@ -38,6 +39,7 @@
 	&mousedevtab,
 	&pipedevtab,
 	&procdevtab,
+	&ramdevtab,
 	&srvdevtab,
 	&ssldevtab,
 	&tlsdevtab,
diff -r c7e9b5edb8d4 src/9vx/trap.c
--- a/src/9vx/trap.c	Sun Dec 27 09:49:22 2009 -0800
+++ b/src/9vx/trap.c	Tue Mar 16 21:29:23 2010 -0700
@@ -198,8 +198,18 @@
 	up->dbgreg = ureg;
 
 	if(up->procctl == Proc_tracesyscall){
+		uint32 *sp = (uint32*)(up->pmmu.uzero + ureg->usp);
 		up->procctl = Proc_stopme;
+		if (up->syscalltrace)
+			free(up->syscalltrace);
+		up->syscalltrace = smprint("%d [%s] %s %#ux %08ux %08ux %08ux %08uxh",
+				up->pid, up->text,
+				sysctab[ureg->ax], sp[0], sp[1], sp[2], sp[3]);
 		procctl(up);
+		/* you must have read the string by now. The free above is really not needed */
+		if (up->syscalltrace)
+			free(up->syscalltrace);
+		up->syscalltrace = NULL;
 	}
 
 	scallnr = ureg->ax;
@@ -260,9 +270,19 @@
 
 	if(up->procctl == Proc_tracesyscall){
 		up->procctl = Proc_stopme;
+		if (up->syscalltrace)
+			free(up->syscalltrace);
+		if(ureg->ax == -1)
+			up->syscalltrace = smprint("= %s\n", up->syserrstr);
+		else
+			up->syscalltrace = smprint("= %#ux\n", ureg->ax);
 		s = splhi();
 		procctl(up);
 		splx(s);
+		/* you must have read the string by now. The free above is really not needed */
+		if (up->syscalltrace)
+			free(up->syscalltrace);
+		up->syscalltrace = NULL;
 	}
 
 	up->insyscall = 0;