lp0 on fire
lp0 on fire (also known as Printer on Fire) is an outdated
Printer flammability
In the late 1950s, high speed computerized printing was still a somewhat experimental field. The first documented fire-starting printer was a
As the technology matured, most large printer installations were
The line printer employed a series of status codes, specifically ready, online, and check. If the online status was set to "off" and the check status was set to "on," the operating system would interpret this as the printer running out of paper. However, if the online code was set to "on" and the check code was also set to "on", it meant that the printer still had paper, but was suffering an error (and may still be attempting to run). Due to the potentially hazardous conditions which could arise in early line printers, UNIX displayed the message "on fire" to motivate any system operator viewing the message to go and check on the line printer immediately.[2]
In the early 1980s,
Phrase origins
Michael K. Johnson ("mkj" of Red Hat and Fedora fame) wrote the first Linux version of this error message in 1992.[3][4] However, he, Herbert Rosmanith and Alan Cox (all Linux developers) have acknowledged that the phrase existed in Unix in different forms prior to his Linux printer implementation.[5][6]
Since then, the
Modern printer drivers and support have improved and hidden low-level error messages from users, so most Unix/Linux users today have never seen the "on fire" message. The "on fire" message remains in the Linux source code as of version 6.0.[7]
The message is also present in other software modules, often to humorous effect. For example, in some kernels' CPU code, a CPU thermal failure could result in the message "CPU#0: Possible thermal failure (CPU on fire ?)"[8] and similar humor can be found in the phrase "halt and catch fire".
See also
References
- ^ "LLNL war story concerning the SC5000 and the Radiation Printer". Retrieved November 14, 2011.
- ^ "Mailing list post relating the history of the lp0 on fire error". Retrieved September 11, 2007.
- ^ "[PATCH] Linux-0.98.3 (October 27, 1992)". GitHub. Retrieved July 30, 2020.
- ^ "Incomplete information - mjk's musings". May 15, 2019. Retrieved May 17, 2019.
- ^ "Linux Kernel Mailing List archive: Michael K. Johnson Re: GLOAT BLOAT (Was: Boot messages, Ideas for v2.1)". June 24, 1996. Retrieved May 17, 2019.
- ^ "Reddit comment from user mcdanlj". May 15, 2019. Retrieved May 17, 2019.
- ^ "lp.c « char « drivers - kernel/git/stable/linux.git - Linux kernel stable tree". git.kernel.org. Retrieved 2022-11-14.
- ^ "CPU#0: Possible thermal failure (CPU on fire ?)". Retrieved December 21, 2014.