ishfield
if (ishfield(linebuf, "to"))
else if (ishfield(linebuf, "subject"))
else if (ishfield(linebuf, "cc"))
else if (ishfield(linebuf, "bcc"))
else if (ishfield(linebuf, "default-options"))
if (ishfield(hdr, "to"))
else if (ishfield(hdr, "subject"))
else if (ishfield(hdr, "cc"))
else if (ishfield(hdr, "bcc"))
else if (ishfield(hdr, "default-options"))
ishfield(linebuf, "status")) {
if (ishfield(linebuf, "content-length")) {
} else if (ishfield(linebuf, "content-type")) {
extern int ishfield(char linebuf[], char field[]);
if (ishfield(linebuf, field))