Red Hat Bugzilla – Bug 59802
Crontab(5) manpage incorrect time specification logic
Last modified: 2007-04-18 12:40:24 EDT
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User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; YIE6)
Description of problem:
One stray word changes the meaning of the statement.
"Commands are executed by cron(8) when the minute,
hour, and month of year fields match the current time, and when at least one of
the two day fields (day of month, or day of week) match the current time"
The second "when" makes the statement say that the command is executed at two
kinds of occasions, when the minute, hour and month specifications math the
current time, and also at any time when one of the two day specifications
match. What is meant is that the command is executed when four out of the five
fields match, and the one that does not match (if any) is one of the day fields.
The logical structure as it stands is like "execution happens when condition A,
and also when condition B is met". What is meant is that execution happens when
conditions A and B are both met simultaneously.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. man 5 crontab.
(i.e. use the '/' key to do text search in the output of 'man'.)
Would it be sufficient to remove the second "when"?
cron.8 will change significantly when we upgrade to cron 4.1 btw.
Err, actually the above sentence no longer appears in cron.8.
It is not in cron.8, it is in cron.5
Of course removing the second 'when' will restore the intended meaning.
Second "when" now removed from crontab.5 in vixie-cron-4.1-8 .