To directly answer the question: man -a (whatever)
may be what you're looking for - this will sequentially and interactively bring up all man pages that match the text you enter, but it will likely bring up way more than you actually wanted.
But your problem is different. Your error message indicates that you have no manpages for qmail
available.
First, ensure that the appropriate manpage packages are installed via yum
. For CentOS 6 these are the packages man man-pages
. For 7 and 8, use man-pages man-db man
.
If those commands installed anything, try man qmail
again.
One thing to note about qmail, is that its documentation is spread out since qmail uses multiple different segmented applications to handle mail delivery. man qmail
will bring up the top-level documentation, and therein you'll be given the names of the other programs which have their own pages such as qmail-control
and qmail-read
.
man man
. It should read "the default action is to search in all of the available sections […], and to show only the first page found". This means ifman qmail
is telling youNo manual entry for qmail
then it's giving you all manual pages forqmail
it knows of: namely zero. Isman -a
(e.g.man -a intro
) good enough? It should give you "all the man sections for", not as "one screen" though.