Where is the manpage of M_PI?

[andrew clarke]

On Thu 2015-06-11 06:20:53 UTC+0200, Nils Kassube (kassube at gmx.net) wrote:

> Peng Yu wrote:
> > > Not exactly, but you can use
> > > 
> > > man math.h
> > > 
> > > if you have the package "libc6-dev" installed.
> > 
> > I don't find `man math.h`. Where is it?
> > 
> > ~$ sudo apt-get install libc6-dev
> 
> > ~$ man math.h
> > No manual entry for math.h
> 
> I think that's a bit strange. Which version of Ubuntu did you try? On my 
> 14.04 machines I can see this:
> 
> ~/ > whereis math.h
> math: /usr/include/math.h
> ~/ > apt-file search /usr/include/math.h
> libc6-dev: /usr/include/math.h

/usr/include/math.h is a C include file, not a manpage.

$ man math.h
No manual entry for math.h

$ man -w
/usr/share/man:/usr/local/man:/usr/local/share/man

$ find /usr/share/man /usr/local/man /usr/local/share/man -iname 'math*'
/usr/share/man/man3/matherr.3.gz
/usr/share/man/man7/math_error.7.gz

$ dpkg -l | grep libc6-dev
ii  libc6-dev:amd64                             2.19-0ubuntu6.6
                  amd64        Embedded GNU C Library: Development
		  Libraries and Header Files
ii  libc6-dev-i386                              2.19-0ubuntu6.6
                  amd64        Embedded GNU C Library: 32-bit
		  development libraries for AMD64
ii  libc6-dev-x32                               2.19-0ubuntu6.6
                  amd64        Embedded GNU C Library: X32 ABI
		  Development Libraries for AMD64

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 14.04.2 LTS
Release:        14.04
Codename:       trusty