如何使“`MANPATH=~/..nmap/doc man 1.nmap”查找nmap.1？

Question

我最近决定，由于我经常试验最新版本的nmap，所以最好在~/.nmap中保持SVN签出，而不安装并运行svn up; make来更新它。我将~/.nmap添加到$PATH中，并刚刚意识到通过这种设置，我不能再运行man nmap了。我在$MANPATH上读了一遍，意识到这似乎不适合我：

[14:51:28][~/.nmap]$ manpath                                          
manpath: warning: $MANPATH set, prepending /etc/man_db.conf
/home/d/virtualenv/share/man:/usr/local/man:/usr/local/share/man:/usr/share/man:/usr/man:/home/d/.nmap/docs/man-xlate/:/home/d/.nmap/docs
[14:51:32][~/.nmap]$ strace  man 1 nmap 2>&1 | egrep 'nmap.1|write'
stat("/home/d/.nmap/docs/zenmap.1", {st_mode=S_IFREG|0664, st_size=5943, ...}) = 0
stat("/home/d/.nmap/docs/nmap.1", {st_mode=S_IFREG|0664, st_size=183621, ...}) = 0
access("/usr/share/man/man1/nmap.1.gz", R_OK) = -1 ENOENT (No such file or directory)
write(2, "No manual entry for nmap in sect"..., 38No manual entry for nmap in section 1

那是为什么，我怎样才能修好它？我注意到man也在~/.nmap/docs中查找一个名为index.db的文件，但找不到它，也许这是一条线索？

Answer 1

问题是，docs目录没有man所需的目录结构(nmap.1应该位于man1子目录中)，与使用-M选项时相同：

    -M path, --manpath=path
          Specify an alternate manpath to use.  By default,  man  uses
          manpath  derived code to determine the path to search.  This
          option  overrides  the  $MANPATH  environment  variable  and
          causes option -m to be ignored.

          A  path  specified as a manpath must be the root of a manual
          page hierarchy structured into sections as described in  the
          man-db  manual  (under  "The  manual page system").  To view
          manual pages outside such hierarchies, see the -l option.

使用make install时，手册将安装到正确的类别子目录中。因此，将MANPATH直接指向docs目录是行不通的。