用途
它是用来显示开头或结尾某个数量的文字区块
全称
head的全称即为head
参数
-q ：隐藏文件名
-v :显示文件名
-c :<字节>显示字节数
-n :<行数>显示的行数
案例
案例一：显示文件/etc/man_db.conf 的前5行
[root@bigdata ~]# head -n 5 /etc/man_db.conf
#
#
# This file is used by the man-db package to configure the man and cat paths.
# It is also used to provide a manpath for those without one by examining
# their PATH environment variable. For details see the manpath(5) man page.
案例二：显示文件/etc/man_db.conf 除了最后5行所有的内容
[root@bigdata ~]# head -n -5 /etc/man_db.conf
#
#
# This file is used by the man-db package to configure the man and cat paths.
# It is also used to provide a manpath for those without one by examining
# their PATH environment variable. For details see the manpath(5) man page.
#
…..
案例三：显示文件/etc/man_db.conf 前100个字节
[root@bigdata ~]# head -c 100 /etc/man_db.conf
#
#
# This file is used by the man-db package to configure the man and cat paths.
案例二：显示文件/etc/man_db.conf 除了最后100个字节外所有的内容
[root@bigdata ~]# head -c -100 /etc/man_db.conf
#
#
# This file is used by the man-db package to configure the man and cat paths.
# It is also used to provide a manpath for those without one by examining
# their PATH environment variable. For details see the manpath(5) man page.
#
# Lines beginning with `#' are comments and are ignored. Any combination of
# tabs or spaces may be used as `whitespace' separators.
#
# There are three mappings allowed in this file:
……