See example checklp.c
Don't use termios to control printer port.
Use ioctl and inb/outb if necessary.
Use Epson, Postscript, PCL, etc. commands to control printer.
<linux/lp.h>
ioctl calls: LPCHAR, LPTIME, LPABORT, LPSETIRQ, LPGETIRQ, LPWAIT
inb/outb for status and control port.