Bug 194601 - lround(3) rounding mode description is wrong
Summary: lround(3) rounding mode description is wrong
Status: RESOLVED CODE_FIX
Alias: None
Product: Documentation
Classification: Unclassified
Component: man-pages (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: documentation_man-pages@kernel-bugs.osdl.org
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-02-15 16:37 UTC by David Eckardt
Modified: 2017-09-28 06:58 UTC (History)
1 user (show)

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Regression: No
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Description David Eckardt 2017-02-15 16:37:30 UTC 
The lround(3) manpage implies it rounds all numbers away from zero. This is wrong: It rounds only halfway cases away from zero.
Comment 1 Michael Kerrisk 2017-09-24 07:55:33 UTC 
Thanks for the report. I changed the opening sentence to read:

       These functions round their argument to the nearest integer value,
       rounding halfway cases away from zero, regardless of  the  current
       rounding direction (see fenv(3)).
Comment 2 David Eckardt 2017-09-26 17:00:05 UTC 
I'm glad to help. Note that not only the sentence you changed is affected but also the NAME section, which incorrectly says:

"lround, lroundf, lroundl, llround, llroundf, llroundl - round to nearest integer, away from zero"

Just for the sake of completeness, I you probably corrected that, too.
Comment 3 Michael Kerrisk 2017-09-28 06:58:38 UTC 
Fair enough. But, I decided to just remove the words "away from zero". The reader can of course discover the details in the text.
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