README for lp_server
====================

Fri May 30 09:40:17 PDT 1997

This program allows you to 'export' a printer on your local host
to be used by an LPRng spooler.  It is basically simulating an
HP JetDirect interface,  which opens a connection on port 9100
and simply dumps input to the PostScript Engine.

```lp_server [-n port] [-t stty_options] [-d device]```

* ```-n port``` - listen (bind) to this port for incoming connections
* ```-d device```  - the device to open
* ```-t stty_options``` - a list of stty options, similar (i.e.- identical)
  to those used by other filters supplied with LPRng.

Build Notes
-----------

(added 25 Jan 2024)

```CFLAGS="-std=c90" ./configure && make && make install```

a systemd unit file for use, tested on Raspberry Pi OS (change device
node to suit, and create a unit file for each printer):

```
[Unit]
Description=JetDirect-compatible server
After=network.target

[Service]
Type=simple
ExecStart=/usr/local/lib/filters/lp_server -n 9100 -d /dev/lp/printers/usb-Hewlett-Packard_hp_LaserJet_1320_series_00CNHC57V00Y
KillMode=process
Restart=on-failure

[Install]
WantedBy=multi-user.target
```

a udev rules file for persistent device nodes for USB printers...drop into /etc/udev/rules.d/99-printers.rules:

```
ACTION=="remove", GOTO="persistent_printer_end"

SUBSYSTEMS=="usb", IMPORT{builtin}="usb_id"
ENV{ID_TYPE}!="printer", GOTO="persistent_printer_end"

ENV{ID_SERIAL}=="?*", SYMLINK+="lp/printers/$env{ID_BUS}-$env{ID_SERIAL}"

LABEL="persistent_printer_end"
```

extra steps for building on Alpine Linux:

```doas apk add gcc musl-dev autoconf make patch && patch -p0 <lp_server-no-glibc.patch```