pappl-mainloop(3)

💖 pappl-mainloop — pappl main loop functions 💖

okay bestie, listen up: this is pappl-mainloop(3) from the pappl main loop functions manual, and it's genuinely the ✨main character✨ of getting a printer application off the ground. no cap.

---

📚 LIBRARY

Printer Application Framework — aka libpappl, and you get at it like this:

pkg-config --cflags --libs pappl

periodt. that's the whole vibe check for linking. 🎀

---

✨ SYNOPSIS ✨

#include <pappl/pappl.h>

int
papplMainloop(int argc, char *argv[], const char *version, const char
*footer_html, int num_drivers, pappl_driver_t *drivers,
pappl_driver_cb_t driver_cb, pappl_ml_autoadd_cb_t autoadd_cb, const
char *subcmd_name, pappl_ml_subcmd_cb_t subcmd_cb, pappl_ml_system_cb_t
system_cb, pappl_ml_usage_cb_t usage_cb, void *data);

like… look at that signature. it's giving comprehensive. 💅

---

🌸 DESCRIPTION 🌸

the mainloop function starts the printer application and supports all the standard command-line arguments and behaviors. that's it, that's the job — but it's a big job and she does it flawlessly. 👑

---

🔥 FUNCTIONS 🔥

🦋 papplMainloop

run a standard main loop for printer applications. yes queen, the standard one. 🫶

int  papplMainloop (
    int argc,
    char *argv[],
    const char *version,
    const char *footer_html,
    int num_drivers,
    pappl_pr_driver_t *drivers,
    pappl_pr_autoadd_cb_t autoadd_cb,
    pappl_pr_driver_cb_t driver_cb,
    const char *subcmd_name,
    pappl_ml_subcmd_cb_t subcmd_cb,
    pappl_ml_system_cb_t system_cb,
    pappl_ml_usage_cb_t usage_cb,
    void *data
);

so this function runs a standard main loop for a printer application. the argc and argv arguments are the ones your main function got handed — yeah, just pass them straight through, no thoughts head empty. 🙈

• version — a numeric version number for your printer application. it needs to play nice with semantic versioning guidelines and can have up to four numbers, like "1.2.3.4". four! iconic.
• footer_html — HTML text that goes in the footer of the web interface. if it's NULL, the footer just… doesn't happen. omitted. ghosted. 💀
• num_drivers, drivers, driver_cb — these three together specify a list of drivers plus the driver callback for printers. if your drivers are configured in the system callback, specify 0 and NULL. don't be out here passing garbage, bestie.
• autoadd_cb — a callback for automatically adding new printers with the autoadd sub-command, and also for auto-detecting the driver when you're adding a printer manually. multitasking queen. 💅
• usage_cb — a callback that displays a usage/help summary. if it's NULL, you get a generic summary shown as needed. it's fine. it's giving default. ✨
• subcmd_name and subcmd_cb — the name and a callback for a custom sub-command. if it's NULL, no custom sub-commands will be supported. that's the deal, no negotiation. 🎀
• system_cb — a function that will create a new pappl_system_t object. if it's NULL, a default system object gets created for you. lowkey convenient. 🌈
• data — application-specific data that gets handed to each of the callbacks. your little bag of secrets, passed around to everyone. 🍓

---

💜 papplMainloopShutdown

request a shutdown of a running system. like texting "omw home" but for a daemon. 😌

void papplMainloopShutdown (void);

this function requests that the system started by papplMainloop be shutdown. that's the whole thing. no arguments, no drama, just closure. 🦋

---

⭐ TYPES ⭐

pappl_ml_subcmd_cb_t — Sub-command callback

typedef int (*pappl_ml_subcmd_cb_t)(const char *base_name, int num_options, cups_option_t *options, int num_files, char **files, void *data);

pappl_ml_system_cb_t — System callback

typedef pappl_system_t * (*pappl_ml_system_cb_t)(int num_options, cups_option_t *options, void *data);

pappl_ml_usage_cb_t — Program usage callback

typedef void (*pappl_ml_usage_cb_t)(void *data);

three little typedefs, all doing their own thing, all slaying separately. 👑

---

👀 SEE ALSO 👀

go read these next, i'm literally begging you:

• pappl(1)
• pappl-client(3)
• pappl-device(3)
• pappl-job(3)
• pappl-log(3)
• pappl-mainline(3)
• pappl-makeresheader(1)
• pappl-printer(3)
• pappl-resource(3)
• pappl-system(3)
• https://www.msweet.org/pappl

---

📜 COPYRIGHT 📜

Copyright © 2019-2022 by Michael R Sweet.

PAPPL is licensed under the Apache License Version 2.0 with an (optional) exception to allow linking against GPL2/LGPL2 software (like older versions of CUPS), so it can be used freely in any project you'd like. see the files LICENSE and NOTICE in the source distribution for more information. 💖

---

fr fr, that's the whole page. go forth and build your printer application, bestie. 🫶✨

and that's a wrap on this edition, babes — the page says pappl-mainloop(3), pappl main loop functions, and it's dated 2026-08-11. mwah. 💅🎀