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Ubuntu每次打开终端出现错误提示的解决方法

发布时间:2016-07-01 15:51:25来源:linux网站作者:jeremy201606
每次打开终端会出现问题,那就说明bashrc文件出现问题。
 
第一步,排除法,确定是哪个用户的哪个bashrc文件出现问题
切换到root用户登陆,打开终端,结果没有出现问题,说明问题出现在jeremy用户上。
切回jeremy用户,寻找是哪个bashrc文件,将/home/jeremy/.bashrc的bashrc文件移动到其他文件夹,结果打开后,错误消失,说明,问题出现在这个文件。
 
第二步,研究这个文件哪里调用了ovs-vsctl命令
.bashrc文件的内容如下:
# ~/.bashrc: executed by bash(1) for non-login shells.  
# see /usr/share/doc/bash/examples/startup-files (in the package bash-doc)  
# for examples
# If not running interactively, don't do anything  
case $- in  
*i*) ;;  
*) return;;  
esac
# don't put duplicate lines or lines starting with space in the history.  
# See bash(1) for more options  
HISTCONTROL=ignoreboth  
# append to the history file, don't overwrite it  
shopt -s histappend  
# for setting history length see HISTSIZE and HISTFILESIZE in bash(1)  
HISTSIZE=1000  
HISTFILESIZE=2000  
# check the window size after each command and, if necessary,  
# update the values of LINES and COLUMNS.  
shopt -s checkwinsize  
# If set, the pattern "**" used in a pathname expansion context will  
# match all files and zero or more directories and subdirectories.  
#shopt -s globstar  
# make less more friendly for non-text input files, see lesspipe(1)  
[ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"  
# set variable identifying the chroot you work in (used in the prompt below)  
if [ -z "${debian_chroot:-}" ] && [ -r /etc/debian_chroot ]; then  
debian_chroot=$(cat /etc/debian_chroot)  
fi  
# set a fancy prompt (non-color, unless we know we "want" color)  
case "$TERM" in  
xterm-color) color_prompt=yes;;  
esac  
# uncomment for a colored prompt, if the terminal has the capability; turned  
# off by default to not distract the user: the focus in a terminal window  
# should be on the output of commands, not on the prompt  
#force_color_prompt=yes  
if [ -n "$force_color_prompt" ]; then  
if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then  
# We have color support; assume it's compliant with Ecma-48  
# (ISO/IEC-6429). (Lack of such support is extremely rare, and such  
# a case would tend to support setf rather than setaf.)  
color_prompt=yes  
else  
color_prompt=  
fi  
fi  
if [ "$color_prompt" = yes ]; then  
PS1='${debian_chroot:+($debian_chroot)}
\033[01;32m
\u@\h
\033[00m
:
\033[01;34m
\w
\033[00m
\$ '  
else  
PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '  
fi  
unset color_prompt force_color_prompt  
# If this is an xterm set the title to user@host:dir  
case "$TERM" in  
xterm*|rxvt*)  
PS1="
\e]0;$debianchroot:+($debianchroot)\u@\h:\w\a
$PS1"  
;;  
*)  
;;  
esac  
# enable color support of ls and also add handy aliases  
if [ -x /usr/bin/dircolors ]; then  
test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"  
alias ls='ls --color=auto'  
#alias dir='dir --color=auto'  
#alias vdir='vdir --color=auto'  
alias grep='grep --color=auto'  
alias fgrep='fgrep --color=auto'  
alias egrep='egrep --color=auto'  
fi  
# some more ls aliases  
alias ll='ls -alF'  
alias la='ls -A'  
alias l='ls -CF'  
# Add an "alert" alias for long running commands.  Use like so:  
#   sleep 10; alert  
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'  
# Alias definitions.  
# You may want to put all your additions into a separate file like  
# ~/.bash_aliases, instead of adding them here directly.  
# See /usr/share/doc/bash-doc/examples in the bash-doc package.  
if [ -f ~/.bash_aliases ]; then  
. ~/.bash_aliases  
fi  
# enable programmable completion features (you don't need to enable  
# this, if it's already enabled in /etc/bash.bashrc and /etc/profile  
# sources /etc/bash.bashrc).  
if ! shopt -oq posix; then  
if [ -f /usr/share/bash-completion/bash_completion ]; then  
. /usr/share/bash-completion/bash_completion  
elif [ -f /etc/bash_completion ]; then  
. /etc/bash_completion  
fi  
fi
先搜索ovs系列的语句,结果在这个文件里面没找到,说明这个文件调用了其他文件的ovs命令,接下来只需查找调用其他文件的执行命令,这里不需要一步一步的看,我的方法是,注释一段语句,再打开终端,如果问题没有出现了,就说明问题就出现在这段语句中。经过直觉的判断,我直接注释了最后一段if语句:
if ! shopt -oq posix; then
if [ -f /usr/share/bash-completion/bash_completion ]; then
. /usr/share/bash-completion/bash_completion
elif [ -f /etc/bash_completion ]; then
. /etc/bash_completion
fi
fi
结果问题没有了,仔细看这段if语句,它的大意是如果/usr/share/bash-completion/bash_completion这个文件存在,就执行这个文件,这就说明问题出现在bash_completion这个文件里面。
 
第三步,继续查找/usr/share/bash-completion/bash_completion出现的问题
这个sh文件有1000多行,刚开始被吓到,但还是有套路的,先搜索ovs,结果没找到,说明还是继续调用的其他ovs文件。仔细扫了一遍之后,发现里面大部分是函数,所以函数部分不用看,直接从执行部分看起,还是按照第二步来,查看调用其他sh文件的语句,结果找到这段if语句:
if [[ -d $BASH_COMPLETION_COMPAT_DIR && -r $BASH_COMPLETION_COMPAT_DIR && \
-x $BASH_COMPLETION_COMPAT_DIR ]]; then
for i in $(LC_ALL=C command ls "$BASH_COMPLETION_COMPAT_DIR"); do
i=$BASH_COMPLETION_COMPAT_DIR/$i
[[ ${i##*/} != @($_backup_glob|Makefile*|$_blacklist_glob) \
&& -f $i && -r $i ]] && . "$i"
done
fi
而BASH_COMPLETION_COMPAT_DIR=/etc/bash_completion.d
所以直接进入/etc/bash_completion.d查找文件,结果找到。
发现ovs*文件,问题就出现在这里,把关于ovs*的文件移出到其他文件后,打开终端就没有问题了。
问题就到这里解决。
 
第四步:总结
如果每次打开终端,都会出现问题,就可以判断出问题出现在~/.bashrc文件,然后再一一筛除。
 
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