whatis 用于查询一个命令执行什么功能，并将查询结果打印到终端上 which 查看可执行文件的位置 whereis 查看文件的位置 man Linux提供了丰富的帮助手册，当你需要查看某个命令的参数时不必到处上网查找，只要man一下即可 locate 配 合数据库查看文件位置 find 实际搜寻硬盘查询文件名称 type 用来区分某个命令是否是shell自带的
whatis whatis 用于查询一个命令执行什么功能，并将查询结果打印到终端上 whatis whatis whatis (1) - display one-line manual page descr... whatis which which (1) - locate a command whatis whereis whereis (1) - locate the binary, source, and man... whatis man man (1) - an interface to the on-line refere... man (7) - macros to format man pages whatis locate locate (1) - find files by name whatis find find (1) - search for files in a directory hi... whatis type type: nothing appropriate. whatis who who (1) - show who is logged on whatis top top (1) - display Linux processes which which命令是查找这个命令是否存在系统中,以及命令存放的位置在哪儿. which whatis /usr/bin/whatis which which /usr/bin/which which whereis /usr/bin/whereis which man /usr/bin/man which locate /usr/bin/locate which find /usr/bin/find which type which ls /bin/ls which cat /bin/cat which top /usr/bin/top which python /usr/bin/python which python3 /usr/bin/python3 which pip /usr/bin/pip which mysql /usr/bin/mysql which mysqld /usr/sbin/mysqld which vim /usr/bin/vim which sqlite whereis whereis命令只能用于搜索程序名，而且只搜索二进制文件（参数-b）、man说明文件（参数-m）和源代码文件（参数-s）。如果省略参数，则返回所有信息。 whereis whatis whatis: /usr/bin/whatis /usr/share/man/man1/whatis.1.gz whereis which which: /usr/bin/which /bin/which /usr/share/man/man1/which.1.gz whereis whereis whereis: /usr/bin/whereis /usr/share/man/man1/whereis.1.gz whereis man man: /usr/bin/man /usr/local/man /usr/share/man /usr/share/man/man1/man.1.gz /usr/share/man/man7/man.7.gz whereis locate locate: /usr/bin/locate /usr/share/man/man1/locate.1.gz whereis find find: /usr/bin/find /usr/share/man/man1/find.1.gz /usr/share/info/find.info.gz whereis type type: whereis vim vim: /usr/bin/vim.basic /usr/bin/vim /usr/bin/vim.tiny /etc/vim /usr/share/vim /usr/share/man/man1/vim.1.gz whereis mysql mysql: /usr/bin/mysql /usr/lib/mysql /etc/mysql /usr/include/mysql /usr/share/mysql /usr/share/man/man1/mysql.1.gz whereis mysqld -b mysqld: /usr/sbin/mysqld /usr/share/man/man8/mysqld.8.gz whereis mysqld mysqld: /usr/sbin/mysqld /usr/share/man/man8/mysqld.8.gz whereis python python: /usr/bin/python /usr/bin/python3.5m /usr/bin/python3.5 /usr/bin/python2.7 /usr/bin/python2.7-config /usr/lib/python3.5 /usr/lib/python2.7 /etc/python /etc/python3.5 /etc/python2.7 /usr/local/lib/python3.5 /usr/local/lib/python2.7 /usr/include/python3.5m /usr/include/python2.7 /usr/share/python /usr/share/man/man1/python.1.gz whereis python2 python2: /usr/bin/python2 /usr/bin/python2.7 /usr/bin/python2.7-config /usr/lib/python2.7 /etc/python2.7 /usr/local/lib/python2.7 /usr/include/python2.7 /usr/share/man/man1/python2.1.gz whereis python3 python3: /usr/bin/python3.5m /usr/bin/python3 /usr/bin/python3.5 /usr/lib/python3 /usr/lib/python3.5 /etc/python3 /etc/python3.5 /usr/local/lib/python3.5 /usr/include/python3.5m /usr/share/python3 /usr/share/man/man1/python3.1.gz man man 是 Linux提供了丰富的帮助手册，当你需要查看某个命令的参数时不必到处上 man whatis output a lot man which output a lot man whereis output a lot man man output a lot man locate output a lot man find output a lot man type No manual entry for type locate locate命令不是实时查找，所以查找的结果不精确，但查找速度很快。因为它查找的不是目录，而是一个数据库（/var/lib/locatedb），这个数据库中含有本地所有文件信息。Linux系统自动创建这个数据库，并且每天自动更新一次，所以使用locate命令查不到最新变动过的文件。为了避免这种情况，可以在使用locate之前，先使用updatedb命令，手动更新数据库。 sudo updatedb locate whatis output a lot locate which output a lot locate whereis /usr/bin/whereis /usr/share/bash-completion/completions/whereis /usr/share/man/man1/whereis.1.gz locate man output a lot locate locate output a lot locate find output a lot locate type output a lot locate passwd will output a lot locate -n 5 passwd /etc/passwd /etc/passwd- /etc/cron.daily/passwd /etc/init/passwd.conf /etc/pam.d/chpasswd locate vim output a lot find find是最常用和最强大的查找命令。它能做到实时查找，精确查找，但速度慢。 find的使用格式如下： #find [指定目录] [指定条件] [指定动作] 指定目录：是指所要搜索的目录和其子目录。如果不指定，则默认为当前目录。 指定条件：是指所要搜索的文件的特点。 指定动作：是指对搜索的结果如何处理。 常见选项: -name 根据文件名称查找（严格区分大小写，如果文件名中间有空格，则必须把文件名用双引号引起来） -iname 根据文件名查找（不区分大小写） -regex “PATTERN” 正则表达式匹配 -user 根据文件属主进行查找 -group 根据文件属组进行查找 -uid 根据文件的uid查找 -gid 根据用户的gid查找 -nouser 查看所有的没有属主的文件 -nogroup 查看所有的没有属组的文件 find whatis find: ‘whatis’: No such file or directory find which find: ‘which’: No such file or directory find whereis find: ‘whereis’: No such file or directory find man find: ‘man’: No such file or directory find locate find: ‘locate’: No such file or directory find find find: ‘find’: No such file or directory find type find: ‘type’: No such file or directory type type命令用来区分某个命令到底是由shell自带的，还是由shell外部的独立二进制文件提供的。如果一个命令是外部命令，那么使用-p参数，会显示该命令的路径，相当于which命令。 type whatis whatis is hashed (/usr/bin/whatis) type which which is hashed (/usr/bin/which) type whereis whereis is hashed (/usr/bin/whereis) type man man is hashed (/usr/bin/man) type locate locate is hashed (/usr/bin/locate) type find find is hashed (/usr/bin/find) type type type is a shell builtin type cd cd is a shell builtin type grep grep is aliased to `grep --color=auto' type cat cat is /bin/cat type vim vim is hashed (/usr/bin/vim) type -p vim /usr/bin/vim type python python is /usr/bin/python转载于:https://www.cnblogs.com/vercont/p/10210155.html
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