Linux Bible

Bash

||, &&, <, >, =, ==, =~, -n, -z, -lt, -eq, -ne
<, >, = (字符串比较，双括号不需要转移) [ "${name}" \> "a" -o "${name}" \< "m" ]  [[ "${name}" > "a" && "${name}" < "m" ]]
"t=""abc123""
""$t"" == abc*  true (globabing 比较）
""$t"" == ""abc*""  false (字面比较)
[[ ""$t"" =~ [abc]+[123]+ ]] true (正则表达式比较)
""$t"" =~ ""abc*""  false (字面比较)
r=""a b+""
""a bbb"" =~ $r  true"

Var OP

${test##*/}  获取文件名
${test%/*}   获取目录名

${#var_name}		$var_name 的字符串长度					
${var:n1}		截取变量var从n1开始的字符					
${var:n1:n2}		截取变量var从n1开始的n2个字符					
${var#substring}	从变量$string的开头, 删除最短匹配$substring的子串					
${var##substring}	从变量$string的开头, 删除最长匹配$substring的子串					
${var#*string}		从左向右截取第一个string后的字符串					
${var##*string}	从左向右截取最后一个string后的字符串					
${var%substring}	从变量$string的结尾, 删除最短匹配$substring的子串 					
${var%%substring}	从变量$string的结尾, 删除最长匹配$substring的子串					
${var%string*}		从右向左截取第一个string后的字符串					
${var%%string*}	从右向左截取最后一个string后的字符串					
${string/substr/rplacemnt}			使用 $rplacemnt, 来代替第一个匹配的 $substr				
${string//substr/rplacemnt}			使用 $rplacemnt, 代替所有匹配的 $substr				
${string/#substr/rplacemnt}			前缀匹配 $substring, 用 $rplacemnt 来代替匹配				
${string/%substr/rplacemnt}			后缀匹配 $substring, 用 $rplacemnt 来代替匹配

\[\e[F;Bm\]........\[\e[0m\]					
/etc/DIR_COLORS => ~/.dir_colors					

F	B				
30	40	黑色			
31	41	红色			
32	42	绿色			
33	43	黄色			
34	44	蓝色			
35	45	紫红色			
36	46	青蓝色			
37	47	白色			

diff <(wget -o - url1) <(wget -o - url2)

Array

定义:
declare -A array1
declare -a 显示所有数组

赋值:
array1=(value1 value2 value3)
或
array1[0]=value1
array1[1]=value2

变量	取值
echo ${array1[0]}	数组第一个元素
echo ${array1[@]} 或 echo ${array1[*]}	数组所有元素
echo ${#array1[@]}	数组元素个数
echo ${!array1[@]}	数组所有索引下标
echo ${array1[@]:1}	数组索引1以后的元素
echo ${array1[@]:1:2}	数组索引1以后2个元素
declare -a	查看所有普通数组

sed

sed -n '/^-----BEGIN CERTIFICATE-----/,/^-----END CERTIFICATE-----$/p' server.crt
sed -i "/^172.*/s/^172.*$/$netip/" "$xfile"
sed -i "s/dpAclBlacklist/dpAclBlocklist/g" dpMgr/src/dpAclMgr.cpp

awk

ARGC   命令行变元个数 
ARGV   命令行变元数组 
FILENAME   当前输入文件名 
FNR   当前文件中的记录号 
FS   输入域分隔符，默认为一个空格 
RS   输入记录分隔符 
NF   当前记录里域个数 
NR   到目前为止记录数 
OFS   输出域分隔符 
ORS   输出记录分隔符 

计算文件第3列的和
awk '{ x += $3 } END { print x }' myfile.txt
awk -F, 'NF>1 {OFS="%";i=1; while(i<NF) {print $1,$i; i++}}' < input.txt
awk -F, 'BEGIN {print ARGC} NF>1 {OFS="%";i=1; while(i<NF) {print $1,$i; i++}}'
awk '/101/,/105/' file
awk '$1 * $2 >100 ' file
awk '{gsub(/\$/,"");gsub(/,/,""); 
   if ($4>1000&&$4<2000) c1+=$4; 
   else if ($4>2000&&$4<3000) c2+=$4; 
   else if ($4>3000&&$4<4000) c3+=$4; 
   else c4+=$4; } 
   END {printf  "c1=[%d];c2=[%d];c3=[%d];c4=[%d]\n",c1,c2,c3,c4}"'

VS Code

${workspaceFolder}/**
${workspaceFolder}/../
/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/src
/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/install-vpp-native/external/include/dpdk/**
/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/install-vpp-native/external/include/dpdk/**
/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/build-vpp-native/vpp
/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/build-vpp-native/vpp/include
/home/jim/projects/mdp-vpp/common/mdplib/log
/home/jim/projects/mdp-vpp/common/mdplib/lib

"${workspaceFolder}/**",
"${workspaceFolder}/../",
"${workspaceFolder}/../../../security/fastpath/dpdk",
"${workspaceFolder}/../../../slowpath/dpdk/inc",
"${workspaceFolder}/../../../../mmx/inc",
"/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/src",
"/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/install-vpp-native/external/include/dpdk/**",
"/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/install-vpp-native/external/include/dpdk/**",
"/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/build-vpp-native/vpp",
"/home/jim/projects/mdp-vpp/fp-vpp/build-vpp-data/vpp/build-root/build-vpp-native/vpp/include",
"/home/jim/projects/mdp-vpp/common/mdplib/log",
"/home/jim/projects/mdp-vpp/common/mdplib/lib",
"/home/jim/projects/mdp-vpp/common/mdplib/event"