What is the true identity of the mysterious Ubuntu bug that 'makes it impossible to print on Tuesdays'?
There is a famous bug in the Linux OS distribution
Comment #28 : Bug #255161 : Bugs : cupsys package : Ubuntu
https://bugs.launchpad.net/ubuntu/+source/cupsys/+bug/255161/comments/28
Many Linux systems, including Ubuntu, use a common printing system called CUPS . CUPS is a standard software stack that sends print data such as PDF to a printer, and consists of a filter system that converts print data into a format that the printer can understand, and a backend system that sends that data to the printer.
In the forum 'Bug #255161' about the package 'cupsys' that was once used in Ubuntu, comments have been posted about the numerous printing-related problems that had been reported with cupsys.
In a forum post from April 2009, Ubuntu user Steve reported, 'My wife was complaining that OpenOffice wouldn't print on Tuesdays. I tried it, and it did indeed not print on Tuesdays.' According to the report, the 'Tuesday printing bug' only occurred when trying to print documents created with OpenOffice , which was once the standard office software for Ubuntu, but other applications printed without issue.
Steve suspected the problem lay in the process of converting documents to PostScript format and identifying whether the file is PostScript, a process that occurs during most printing processes. When he looked at the intermediate files converted to PostScript format, he noticed that the CreationDate tag contained the word 'Tue,' which indicates the day of the week. Attempting to print a file containing 'Tue' failed, but when he changed 'Tue' to 'XTue' and saved the file, it printed without issue. Steve pointed out that this problem did not occur in applications other than OpenOffice because the CreationDate tag was omitted.
The reason why printing doesn't occur when 'Tue' is included lies in the process later in the printing process, which is to 'identify whether the file is PostScript or not.' After converting the document to PostScript format, the 'file' command is used to check whether the file is in a printable PostScript format. However, the bug occurs when the internal byte sequence pattern matching process mistakenly identifies the file as a 'different file format' only if the PostScript format CreationDate tag contains 'Tue.'
A similar 'Tuesday printing' bug was reported in Bug #248619 , which explains that 'the file's fourth byte contains 'Tue', indicating that it is an Erlang JAM file, which is different from PostScript format.' Bug #248619 was fixed in the official October 2009 release of Ubuntu 9.10.
The 'cannot print on Tuesdays' bug is an old one, having been reported and fixed around 2008-2009. However, it is often mentioned as an example of a seemingly mysterious phenomenon, but the cause can be clearly identified through technical analysis, such as ' your car won't start only when you buy vanilla ice cream ' or ' your PC wakes up from sleep mode when you change clothes in your room .'
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in Software, Posted by log1e_dh