/* * We assume there's only one error buffer for the whole system. * If you use ffork, you need to provide a _syserrstr.  Since most * people will use libthread (which provides a _syserrstr), this is * okay. */ #include <u.h>#include <errno.h>#include <string.h>#include <libc.h> enum{	EPLAN9 = 0x19283745}; char *(*_syserrstr)(void);static char xsyserr[ERRMAX];static char*getsyserr(void){	char *s; 	s = nil;	if(_syserrstr)		s = (*_syserrstr)();	if(s == nil)		s = xsyserr;	return s;} interrstr(char *err, uint n){	char tmp[ERRMAX];	char *syserr; 	strecpy(tmp, tmp+ERRMAX, err);	rerrstr(err, n);	syserr = getsyserr();	strecpy(syserr, syserr+ERRMAX, tmp);	errno = EPLAN9;	return 0;} voidrerrstr(char *err, uint n){	char *syserr; 	syserr = getsyserr();	if(errno == EINTR)		strcpy(syserr, "interrupted");	else if(errno != EPLAN9)		strcpy(syserr, strerror(errno));	strecpy(err, err+n, syserr);} /* replaces __errfmt in libfmt */ int__errfmt(Fmt *f){	if(errno == EPLAN9)		return fmtstrcpy(f, getsyserr());	return fmtstrcpy(f, strerror(errno));} voidwerrstr(char *fmt, ...){	va_list arg;	char buf[ERRMAX]; 	va_start(arg, fmt);	vseprint(buf, buf+ERRMAX, fmt, arg);	va_end(arg);	errstr(buf, ERRMAX);}