Linux
history
history用来记录在prompt中输入过的command的列表
history里面记录的命令行数量由HISTSIZE环境变量控制，HISTSIZE在文件/etc/profile或者~/.profile文件中
在个人用户的~/.profile文件中，配置的是当前用户的HISTSIZE数量
这里的umask指的是默认权限遮罩，也就是默认创建的文件中的3个421权限中，后面2个没有2权限，也就是写权限
如果以上经验帮到您，麻烦在左下角给点个赞，谢谢！
这是/etc/prifile文件的内容[root@golonglee ~]# cat /etc/profile# /etc/profile# System wide environment and startup programs, for login setup# Functions and aliases go in /etc/bashrc# It's NOT a good idea to change this file unless you know what you# are doing. It's much better to create a custom.sh shell script in# /etc/profile.d/ to make custom changes to your environment, as this# will prevent the need for merging in future updates.pathmunge () { case ':${PATH}:' in *:'$1':*) ;; *) if [ '$2' = 'after' ] ; then PATH=$PATH:$1 else PATH=$1:$PATH fi esac}if [ -x /usr/bin/id ]; then if [ -z '$EUID' ]; then # ksh workaround EUID=`id -u` UID=`id -ru` fi USER='`id -un`' LOGNAME=$USER MAIL='/var/spool/mail/$USER'fi# Path manipulationif [ '$EUID' = '0' ]; then pathmunge /sbin pathmunge /usr/sbin pathmunge /usr/local/sbinelse pathmunge /usr/local/sbin after pathmunge /usr/sbin after pathmunge /sbin afterfiHOSTNAME=`/bin/hostname 2>/dev/null`HISTSIZE=1000if [ '$HISTCONTROL' = 'ignorespace' ] ; then export HISTCONTROL=ignorebothelse export HISTCONTROL=ignoredupsfiexport PATH USER LOGNAME MAIL HOSTNAME HISTSIZE HISTCONTROL# By default, we want umask to get set. This sets it for login shell# Current threshold for system reserved uid/gids is 200# You could check uidgid reservation validity in# /usr/share/doc/setup-*/uidgid fileif [ $UID -gt 199 ] && [ '`id -gn`' = '`id -un`' ]; then umask 002else umask 022fifor i in /etc/profile.d/*.sh ; do if [ -r '$i' ]; then if [ '${-#*i}' != '$-' ]; then . '$i' else . '$i' >/dev/null 2>&1 fi fidoneunset iunset pathmunge[root@golonglee ~]#