Let's try this. It's BUGGERED.

src/cmd/troff/n2.c

@@ -0,0 +1,325 @@
+/*
+ * n2.c
+ *
+ * output, cleanup
+ */
+
+#include "tdef.h"
+#include "fns.h"
+#include "ext.h"
+#include <setjmp.h>
+
+#ifdef STRICT
+	/* not in ANSI or POSIX */
+FILE*	popen(char*, char*);
+#endif
+
+
+extern	jmp_buf	sjbuf;
+int	toolate;
+int	error;
+
+char	obuf[2*BUFSIZ];
+char	*obufp = obuf;
+
+	/* pipe command structure; allows redicously long commends for .pi */
+struct Pipe {
+	char	*buf;
+	int	tick;
+	int	cnt;
+} Pipe;
+
+
+int	xon	= 0;	/* records if in middle of \X */
+
+int pchar(Tchar i)
+{
+	int j;
+	static int hx = 0;	/* records if have seen HX */
+
+	if (hx) {
+		hx = 0;
+		j = absmot(i);
+		if (isnmot(i)) {
+			if (j > dip->blss)
+				dip->blss = j;
+		} else {
+			if (j > dip->alss)
+				dip->alss = j;
+			ralss = dip->alss;
+		}
+		return 0;
+	}
+	if (ismot(i)) {
+		pchar1(i); 
+		return 0;
+	}
+	switch (j = cbits(i)) {
+	case 0:
+	case IMP:
+	case RIGHT:
+	case LEFT:
+		return 0;
+	case HX:
+		hx = 1;
+		return 0;
+	case XON:
+		xon++;
+		break;
+	case XOFF:
+		xon--;
+		break;
+	case PRESC:
+		if (!xon && !tflg && dip == &d[0])
+			j = eschar;	/* fall through */
+	default:
+		setcbits(i, trtab[j]);
+	}
+	if (NROFF & xon)	/* rob fix for man2html */
+		return 0;
+	pchar1(i);
+	return 0;
+}
+
+
+void pchar1(Tchar i)
+{
+	int j;
+
+	j = cbits(i);
+	if (dip != &d[0]) {
+		wbf(i);
+		dip->op = offset;
+		return;
+	}
+	if (!tflg && !print) {
+		if (j == '\n')
+			dip->alss = dip->blss = 0;
+		return;
+	}
+	if (j == FILLER && !xon)
+		return;
+	if (tflg) {	/* transparent mode, undiverted */
+		if (print)			/* assumes that it's ok to print */
+			/* OUT "%c", j PUT;	/* i.e., is ascii */
+			outascii(i);
+		return;
+	}
+	if (TROFF && ascii)
+		outascii(i);
+	else
+		ptout(i);
+}
+
+
+void outweird(int k)	/* like ptchname() but ascii */
+{
+	char *chn = chname(k);
+
+	switch (chn[0]) {
+	case MBchar:
+		OUT "%s", chn+1 PUT;	/* \n not needed? */
+		break;
+	case Number:
+		OUT "\\N'%s'", chn+1 PUT;
+		break;
+	case Troffchar:
+		if (strlen(chn+1) == 2)
+			OUT "\\(%s", chn+1 PUT;
+		else
+			OUT "\\C'%s'", chn+1 PUT;
+		break;
+	default:
+		OUT " %s? ", chn PUT;
+		break;
+	}
+}
+
+void outascii(Tchar i)	/* print i in best-guess ascii */
+{
+	char *p;
+	int j = cbits(i);
+
+/* is this ever called with NROFF set? probably doesn't work at all. */
+
+	if (ismot(i))
+		oput(' ');
+	else if (j < ALPHABET && j >= ' ' || j == '\n' || j == '\t')
+		oput(j);
+	else if (j == DRAWFCN)
+		oputs("\\D");
+	else if (j == HYPHEN)
+		oput('-');
+	else if (j == MINUS)	/* special pleading for strange encodings */
+		oputs("\\-");
+	else if (j == PRESC)
+		oputs("\\e");
+	else if (j == FILLER)
+		oputs("\\&");
+	else if (j == UNPAD)
+		oputs("\\ ");
+	else if (j == OHC)	/* this will never occur;  stripped out earlier */
+		oputs("\\%");
+	else if (j == XON)
+		oputs("\\X");
+	else if (j == XOFF)
+		oputs(" ");
+	else if (j == LIG_FI)
+		oputs("fi");
+	else if (j == LIG_FL)
+		oputs("fl");
+	else if (j == LIG_FF)
+		oputs("ff");
+	else if (j == LIG_FFI)
+		oputs("ffi");
+	else if (j == LIG_FFL)
+		oputs("ffl");
+	else if (j == WORDSP) {		/* nothing at all */
+		if (xon)		/* except in \X */
+			oput(' ');
+
+	} else
+		outweird(j);
+}
+
+int flusho(void)
+{
+	if (NROFF && !toolate && t.twinit)
+			fwrite(t.twinit, strlen(t.twinit), 1, ptid);
+
+	if (obufp > obuf) {
+		if (pipeflg && !toolate) {
+			/* fprintf(stderr, "Pipe to <%s>\n", Pipe.buf); */
+			if (!Pipe.buf[0] || (ptid = popen(Pipe.buf, "w")) == NULL)
+				ERROR "pipe %s not created.", Pipe.buf WARN;
+			if (Pipe.buf)
+				free(Pipe.buf);
+		}
+		if (!toolate)
+			toolate++;
+		*obufp = 0;
+		fputs(obuf, ptid);
+		fflush(ptid);
+		obufp = obuf;
+	}
+	return 1;
+}
+
+
+void caseex(void)
+{
+	done(0);
+}
+
+
+void done(int x) 
+{
+	int i;
+
+	error |= x;
+	app = ds = lgf = 0;
+	if (i = em) {
+		donef = -1;
+		eschar = '\\';
+		em = 0;
+		if (control(i, 0))
+			longjmp(sjbuf, 1);
+	}
+	if (!nfo)
+		done3(0);
+	mflg = 0;
+	dip = &d[0];
+	if (woff)	/* BUG!!! This isn't set anywhere */
+		wbf((Tchar)0);
+	if (pendw)
+		getword(1);
+	pendnf = 0;
+	if (donef == 1)
+		done1(0);
+	donef = 1;
+	ip = 0;
+	frame = stk;
+	nxf = frame + 1;
+	if (!ejf)
+		tbreak();
+	nflush++;
+	eject((Stack *)0);
+	longjmp(sjbuf, 1);
+}
+
+
+void done1(int x) 
+{
+	error |= x;
+	if (numtabp[NL].val) {
+		trap = 0;
+		eject((Stack *)0);
+		longjmp(sjbuf, 1);
+	}
+	if (!ascii)
+		pttrailer();
+	done2(0);
+}
+
+
+void done2(int x) 
+{
+	ptlead();
+	if (TROFF && !ascii)
+		ptstop();
+	flusho();
+	done3(x);
+}
+
+void done3(int x) 
+{
+	error |= x;
+	flusho();
+	if (NROFF)
+		twdone();
+	if (pipeflg)
+		pclose(ptid);
+	exit(error);
+}
+
+
+void edone(int x) 
+{
+	frame = stk;
+	nxf = frame + 1;
+	ip = 0;
+	done(x);
+}
+
+
+void casepi(void)
+{
+	int j;
+	char buf[NTM];
+
+	if (Pipe.buf == NULL) {
+		if ((Pipe.buf = (char *)calloc(NTM, sizeof(char))) == NULL) {
+			ERROR "No buf space for pipe cmd" WARN;
+			return;
+		}
+		Pipe.tick = 1;
+	} else
+		Pipe.buf[Pipe.cnt++] = '|';
+
+	getline(buf, NTM);
+	j = strlen(buf);
+	if (toolate) {
+		ERROR "Cannot create pipe to %s", buf WARN;
+		return;
+	}
+	Pipe.cnt += j;
+	if (j >= NTM +1) {
+		Pipe.tick++;
+		if ((Pipe.buf = (char *)realloc(Pipe.buf, Pipe.tick * NTM * sizeof(char))) == NULL) {
+			ERROR "No more buf space for pipe cmd" WARN;
+			return;
+		}
+	}
+	strcat(Pipe.buf, buf);
+	pipeflg++;
+}