环境变量

/etc/profile（所有用户生效）
/etc/profile.d/*.sh
~/.bash_profile
~/.bashrc（当前用户生效）
/etc/bashrc

if [ $UID -gt 199 ] && [ "`id -gn`" = "`id -un`" ]; then
    umask 002
else
    umask 022
fi
...
for i in /etc/profile.d/*.sh ; do
    if [ -r "$i" ]; then
        if [ "${-#*i}" != "$-" ]; then
            . "$i"
        else
            . "$i" >/dev/null 2>&1
        fi
    fi
done
[root@localhost ~]# umask
0022

rw-rw-rw-   ----w--w-  r--r--r--
rwxrwxrwx  ----w--w-  rwxr-xr-x（755）

~/.bash_profile
if [ -f ~/.bashrc ]; then
        . ~/.bashrc
fi

~/.bashrc（定义别名）
# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi

PS1变量（起始符）
umask
PASH变量

~/.bash_logout

~/.bash_history

/etc/issue

/etc/issue.net

/etc/ssh/sshd_config
Banner /etc/issue.net

/etc/motd