section.1 start

1.man 命令
linux中最常用的帮助命令就是man，它会在不同的目录中寻找用户所需的手册页，manpath命令显示当前的搜索路径，fc10上面为

/usr/kerberos/man:/usr/local/share/man:/usr/share/man/zh_CN:/usr/share/man


红帽或FC系列可以修改 /etc/man.config
ubuntu suse等是 /etc/manpath.config

2.which 命令  shows the full path of (shell) commands.
用于查找所需要的命令是否已经在相关搜索路径当中

#which gcc
/usr/lib/ccache/gcc
#which firefox
/usr/bin/firefox


3.whereis 命令  locate the binary, source, and manual page files for a command
更大范围的搜索系统目录，和shell的搜索路径无关

# whereis gcc
gcc: /usr/bin/gcc /usr/lib/gcc /usr/libexec/gcc /usr/share/man/man1/gcc.1.gz
＃whereis firefox
firefox: /usr/bin/firefox /usr/share/man/man1/firefox.1.gz

4.locate 命令  find files by name
考察预先编译好的一个文件系统索引，来确定搜索的文件，gcc与firefox结果非常多，查stdio.h

# locate stdio.h
/usr/include/stdio.h
/usr/include/bits/stdio.h
/usr/include/boost/iostreams/filter/stdio.hpp
/usr/include/c++/4.3.2/tr1/stdio.h
/usr/include/glib-2.0/glib/gstdio.h
/usr/include/libgsf-1/gsf/gsf-infile-stdio.h
/usr/include/libgsf-1/gsf/gsf-input-stdio.h
/usr/include/libgsf-1/gsf/gsf-outfile-stdio.h
/usr/include/libgsf-1/gsf/gsf-output-stdio.h
/usr/include/xulrunner-sdk-1.9/system_wrappers/stdio.h
/usr/lib/perl5/5.10.0/i386-linux-thread-multi/CORE/nostdio.h
/usr/share/man/man0p/stdio.h.0p.gz


看来locate命令再查找头文件时比较好用

5.rpm命令 －q 参数 可以查找已安装的rpm包，

＃rpm -q firefox
firefox-3.0.4-1.fc10.i386
＃rpm -q gcc
gcc-4.3.2-7.i386