add linewrap option when encoding (76 columns)

output.c

@@ -0,0 +1,19 @@
+#include "output.h"
+
+#define WRAPCOL 76
+
+char
+printw(FILE *fp, unsigned char *s, int slen)
+{
+    static int col;
+    int c;
+
+    while (slen--) {
+        fputc((c = *s++), fp);
+        ++col;
+        if (!(col %= WRAPCOL))
+            fputc((c = '\n'), fp);
+    }
+
+    return c;
+}