// print system callsdefn printstring(s){	print("\"", s, "\"");} defn printtextordata(addr, n){	local a, i; 	a = addr\c;	i = 0;	loop 1, n do {		if (a[i]>=127) then {			print(fmt(addr, 'X'), ", ", n\D);			return {};		}		i = i+1;	} 	print("\"");	printstringn(addr, n);	print("\"");} defn printstringn(s, n){	local m; 	m = n;	if (m > 100) then m = 100;	loop 1,m do {		print(*(s\c)); s=s+1;	}	if(m != n) then print("...");} defn printsyscall(name, fmt, arg) {	local f, i, a, argp, sl; 	print(name, "(");	i = 0;	a = eval arg;	while fmt[i] != 0 do {		if fmt[i] == 's' then {			if *a == 0 then				print("nil");			else				printstring(*(*a\s));		} else if fmt[i] == 'S' then {			argp = *a;			argl = {};			while *argp != 0 do {				argl = append argl, *(*argp\s);				argp++;			}			print(argl);		} else if (fmt[i] == 'Z') && (~*a == 0) then {			print("-1");			a++;	// advance extra word for quadword		} else if (fmt[i] == 'Y') || (fmt[i] == 'V') then {			print(fmt(*a, fmt[i]));			a++;	// advance extra word for quadword		} else if (fmt[i] == 'T') then {			if *a == 0 then				print("nil");			else				printtextordata(*a, a[1]);		} else			print(fmt(*a, fmt[i]));		if fmt[i+1] != 0 then			print(", ");		i = i+1;		a++;	}	print(")\n");} defn code(*e) { return e; } syscalls = {	{ 0, {"sysr1",		"s",		code(0)}},	{ 1, {"_errstr",		"s",		code(*sys_errstr:arg)}},	{ 2, {"bind",		"ssX",		code(*sysbind:arg)}},	{ 3, {"chdir",		"s",		code(*sysbind:arg)}},	{ 4, {"close",		"D",		code(*sysclose:arg)}},	{ 5, {"dup",		"DD",		code(*sysdup:arg)}},	{ 6, {"alarm",		"D",		code(*sysalarm:arg)}},	{ 7, {"exec",		"sS",		code(*sysexec:arg)}},	{ 8, {"exits",		"s",		code(*sysexits:arg)}},	{ 9, {"_fsession",	"DX",		code(*sys_fsession:arg)}},	{10, {"fauth",		"DX",		code(*sysfauth:arg)}},	{11, {"_fstat",		"DX",		code(*sys_fstat:arg)}},	{12, {"segbrk",		"XX",		code(*syssegbrk:arg)}},	{13, {"_mount",		"DsXs",		code(*sys_mount:arg)}},	{14, {"open",		"sD",		code(*sysopen:arg)}},	{15, {"_read",		"DXD",		code(*sys_read:arg)}},	{16, {"oseek",		"DDD",		code(*sysoseek:arg)}},	{17, {"sleep",		"D",		code(*syssleep:arg)}},	{18, {"_stat",		"sX",		code(*sys_stat:arg)}},	{19, {"rfork",		"X",		code(*sysstat:arg)}},	{20, {"_write",		"DXD",		code(*sys_write:arg)}},	{21, {"pipe",		"X",		code(*syspipe:arg)}},	{22, {"create",		"sDO",		code(*syscreate:arg)}},	{23, {"fd2path",	"DXD",		code(*sysfd2path:arg)}},	{24, {"brk_",		"X",		code(*sysbrk_:arg)}},	{25, {"remove",		"s",		code(*sysremove:arg)}},	{26, {"_wstat",		"sX",		code(*sys_wstat:arg)}},	{27, {"_fwstat",		"DX",		code(*sys_fwstat:arg)}},	{28, {"notify",		"X",		code(*sysnotify:arg)}},	{29, {"noted",		"D",		code(*sysnoted:arg)}},	{30, {"segattach",	"DsXD",		code(*syssegattach:arg)}},	{31, {"segdetach",	"X",		code(*syssegdetach:arg)}},	{32, {"segfree",	"XD",		code(*syssegfree:arg)}},	{33, {"segflush",	"XD",		code(*syssegflush:arg)}},	{34, {"rendezvous",	"XX",		code(*sysrendezvous:arg)}},	{35, {"unmount",	"ss",		code(*sysunmount:arg)}},	{36, {"_wait",		"X",		code(*sys_wait:arg)}},	{39, {"seek",		"XDVD",		code(*sysseek:arg)}},	{40, {"fversion",	"DDsD",		code(*sysfversion:arg)}},	{41, {"errstr",		"TD",		code(*syserrstr:arg)}},	{42, {"stat",		"sXD",		code(*sysstat:arg)}},	{43, {"fstat",		"DXD",		code(*sysfstat:arg)}},	{44, {"wstat",		"sXD",		code(*syswstat:arg)}},	{45, {"fwstat",		"DXD",		code(*sysfwstat:arg)}},	{46, {"mount",		"DDsXs",		code(*sysmount:arg)}},	{47, {"await",		"TD",		code(*sysawait:arg)}},	{50, {"pread",		"DXDZ",		code(*syspread:arg)}},	{51, {"pwrite",		"DTDZ",		code(*syspwrite:arg)}},}; defn syscall() {	local n, sl, h, p; 	map({"*data", 0, 0xffffffff, 0});	n = *syscall:scallnr;	sl = syscalls;	while sl != {} do {		h = head sl;		sl = tail sl; 		if n == h[0] then {			p = h[1];			printsyscall(p[0], p[1], p[2]);		}	}} defn UPCSPRET() {	// return sys call number, address of first argument, location of syscall return value	if objtype == "386" then 		return { code(*(*PC-4)), code(*SP+4), code(*AX) };	if (objtype == "mips") || (objtype == "mips2") then		return { code(*(*PC-4) & 0xffff), code(*SP+4), code(*R1) };	if objtype == "arm" then		return { code(*(*PC-4) & 0xffff), code(*SP+4), code(*R0) };	// untested	if objtype == "alpha" then		return { code(*(*PC-4) & 0xffff), code(*SP+4), code(*R0) };	// untested} defn trapoffset() {	// return offset from entry point to trap instr	if objtype == "386" then return 5;	if objtype == "mips" then return 8;	if objtype == "mips2" then return 8;	if objtype == "arm" then return 8;	// untested	if objtype == "alpha" then return 8;	// untested}	 defn trapreason() {	// return reason for trap	if objtype == "386" then return reason(*TRAP);	if objtype == "mips" then return reason(*CAUSE);	if objtype == "mips2" then return reason(*CAUSE);	if objtype == "arm" then return "unknown trap";	// untested	if objtype == "alpha" then return reason(cause);	// untested}  defn usyscall() {	// gives args for system call in user level; not useful with -k	local n, sl, h, p; 	// stopped at TRAP instruction in system call library	pcsp = UPCSPRET();	n = eval pcsp[0];	sl = syscalls;	while sl != {} do {		h = head sl;		sl = tail sl; 		if n == h[0] then {			p = h[1];			printsyscall(p[0], p[1], pcsp[1]);		}	}}