To rebuild the pages it depends on what your problem is...
To try if the files are still intact, select a command you need the manpage for. Let's say you need the manpage of ls. Then do the following:
cd /usr/share/man
ls -ld man*/ls* (but this can be replaced by any other command)
If it is in a directory ending with .Z, do the following:
zcat
Or, if the directory name does not end with .Z, do:
cat man*/ls* | nroff -man | pg
This should return the manual page you needed.
If this works, take a look for the 'cat' page:
ls -ld cat*/ls*
If this returns a file, look at the permissions and size. Try:
man ls
If this results in nothing, like your problem, remove the cat file:
rm cat*/ls*
and do the man command again:
man ls
This should result in the output: Reformatting man page...
And then the man page you need.
If this works, remove all 'cat' files that don't work, or just all, and you should be fine.
If these steps fail somewhere, and need more help, please inform where it goes wrong, so we can be of more assistance. But perhaps you need to re-install them.
Every problem has at least one solution. Only some solutions are harder to find.
