Make formatting and names more consistent

Signed-off-by: Edwin Kofler <edwin@kofler.dev>
This commit is contained in:
Edwin Kofler 2023-11-18 13:43:12 -08:00
parent 212326d7a3
commit 88e095d5fc
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@ -75,15 +75,15 @@ sudo !!
##### Run last command and change some parameter using caret substitution (e.g. last command: echo 'aaa' -> rerun as: echo 'bbb')
```bash
#last command: echo 'aaa'
# last command: echo 'aaa'
^aaa^bbb
#echo 'bbb'
#bbb
#Notice that only the first aaa will be replaced, if you want to replace all 'aaa', use ':&' to repeat it:
# Notice that only the first aaa will be replaced, if you want to replace all 'aaa', use ':&' to repeat it:
^aaa^bbb^:&
#or
# or
!!:gs/aaa/bbb/
```
@ -218,7 +218,7 @@ echo ${var[@]#0}
##### Grep lines with strings from a file (e.g. lines with 'stringA or 'stringB' or 'stringC')
```bash
#with grep
# with grep
test="stringA stringB stringC"
grep ${test// /\\\|} file.txt
# turning the space into 'or' (\|) in grep
@ -318,7 +318,7 @@ grep -c "^$"
##### Grep and return only integer
```bash
grep -o '[0-9]*'
#or
# or
grep -oP '\d*'
```
##### Grep integer with certain number of digits (e.g. 3)
@ -341,7 +341,7 @@ grep -Po '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}'
```bash
grep -w 'target'
#or using RE
# or using RE
grep '\btarget\b'
```
##### Grep returning lines before and after match (e.g. 'bbo')
@ -379,7 +379,7 @@ grep -v '^#' file.txt
##### Grep variables with space within it (e.g. myvar="some strings")
```bash
grep "$myvar" filename
#remember to quote the variable!
# remember to quote the variable!
```
##### Grep only one/first match (e.g. 'bbo')
@ -458,8 +458,8 @@ grep $'\t'
```bash
$echo "$long_str"|grep -q "$short_str"
if [ $? -eq 0 ]; then echo 'found'; fi
#grep -q will output 0 if match found
#remember to add space between []!
# grep -q will output 0 if match found
# remember to add space between []!
```
##### Grep strings between a bracket()
@ -545,7 +545,7 @@ sed -i '$ s/.$//' filename
##### Add string to beginning of file (e.g. "\[")
```bash
sed -i '1s/^/[/' file
sed -i '1s/^/[/' filename
```
##### Add string at certain line number (e.g. add 'something' to line 1 and line 3)
@ -692,7 +692,7 @@ sed '$ s/.$//'
##### Insert character at specified position of file (e.g. AAAAAA --> AAA#AAA)
```bash
sed -r -e 's/^.{3}/&#/' file
sed -r -e 's/^.{3}/&#/' filename
```
@ -747,7 +747,7 @@ awk -v N=7 '{print}/bbo/&& --N<=0 {exit}'
##### Print filename and last line of all files in directory
```bash
ls|xargs -n1 -I file awk '{s=$0};END{print FILENAME,s}' file
ls|xargs -n1 -I file awk '{s=$0};END{print FILENAME,s}' filename
```
##### Add string to the beginning of a column (e.g add "chr" to column $3)
@ -757,12 +757,12 @@ awk 'BEGIN{OFS="\t"}$3="chr"$3'
##### Remove lines with string (e.g. 'bbo')
```bash
awk '!/bbo/' file
awk '!/bbo/' filename
```
##### Remove last column
```bash
awk 'NF{NF-=1};1' file
awk 'NF{NF-=1};1' filename
```
##### Usage and meaning of NR and FNR
@ -827,7 +827,7 @@ awk '{printf("%s\t%s\n",NR,$0)}'
# David cat
# David dog
awk '{split($2,a,",");for(i in a)print $1"\t"a[i]}' file
awk '{split($2,a,",");for(i in a)print $1"\t"a[i]}' filename
# Detail here: http://stackoverflow.com/questions/33408762/bash-turning-single-comma-separated-column-into-multi-line-string
```
@ -941,7 +941,7 @@ find /dir/to/A -type f -name "*.py" -print 0| xargs -0 -r -I file cp -v -p file
##### With sed
```bash
ls |xargs -n1 -I file sed -i '/^Pos/d' file
ls |xargs -n1 -I file sed -i '/^Pos/d' filename
```
##### Add the file name to the first line of file
@ -1053,8 +1053,8 @@ else
fi
# if variable is null
if [ ! -s "myvariable" ]; then echo -e "variable is null!" ; fi
#True of the length if "STRING" is zero.
if [ ! -s "$myvariable" ]; then echo -e "variable is null!" ; fi
# True of the length if "STRING" is zero.
# Using test command (same as []), to test if the length of variable is nonzero
test -n "$myvariable" && echo myvariable is "$myvariable" || echo myvariable is not set
@ -1091,7 +1091,7 @@ if [[ $age -gt 21 ]]; then echo -e "forever 21!!" ; fi
```bash
# Echo the file name under the current directory
for i in $(ls); do echo file $i; done
#or
# or
for i in *; do echo file $i; done
# Make directories listed in a file (e.g. myfile)
@ -1104,10 +1104,10 @@ for i in $(cat tpc_stats_0925.log |grep failed|grep -o '\query\w\{1,2\}'); do ca
oifs="$IFS"; IFS=$'\n'; for line in $(cat myfile); do ...; done
while read -r line; do ...; done <myfile
#If only one word a line, simply
# If only one word a line, simply
for line in $(cat myfile); do echo $line; read -n1; done
#Loop through an array
# Loop through an array
for i in "${arrayName[@]}"; do echo $i; done
```
@ -1216,7 +1216,7 @@ TMOUT=10
##### Set how long you want to run a command
```bash
#This will run the command 'sleep 10' for only 1 second.
# This will run the command 'sleep 10' for only 1 second.
timeout 1 sleep 10
```
@ -1585,7 +1585,7 @@ who -r
##### Change SysV runlevel (e.g. 5)
```bash
init 5
#or
# or
telinit 5
```
@ -1787,7 +1787,7 @@ pushd .
# then pop
popd
#or use dirs to display the list of currently remembered directories.
# or use dirs to display the list of currently remembered directories.
dirs -l
```
@ -1798,7 +1798,7 @@ df -h
# or
du -h
#or
# or
du -sk /var/log/* |sort -rn |head -10
```
@ -1828,7 +1828,7 @@ runlevel
```bash
init 3
#or
# or
telinit 3
```
@ -2145,7 +2145,7 @@ ps aux|grep python
```bash
ps -p <PID>
#or
# or
cat /proc/<PID>/status
cat /proc/<PID>/stack
cat /proc/<PID>/stat
@ -2193,21 +2193,21 @@ sudo dpkg --purge <package_name>
```bash
ssh -f -L 9000:targetservername:8088 root@192.168.14.72 -N
#-f: run in background; -L: Listen; -N: do nothing
#the 9000 of your computer is now connected to the 8088 port of the targetservername through 192.168.14.72
#so that you can see the content of targetservername:8088 by entering localhost:9000 from your browser.
# the 9000 of your computer is now connected to the 8088 port of the targetservername through 192.168.14.72
# so that you can see the content of targetservername:8088 by entering localhost:9000 from your browser.
```
##### Get process ID of a process (e.g. sublime_text)
```bash
#pidof
# pidof
pidof sublime_text
#pgrep, you don't have to type the whole program name
# pgrep, you don't have to type the whole program name
pgrep sublim
#pgrep, echo 1 if process found, echo 0 if no such process
# pgrep, echo 1 if process found, echo 0 if no such process
pgrep -q sublime_text && echo 1 || echo 0
#top, takes longer time
# top, takes longer time
top|grep sublime_text
```
@ -2490,7 +2490,7 @@ $ sudo nc -l 80
##### Check which ports are listening for TCP connections from the network
```bash
#notice that some companies might not like you using nmap
# note that some companies might not like you using nmap
nmap -sT -O localhost
# check port 0-65535
@ -2498,7 +2498,7 @@ nmap -p0-65535 localhost
```
##### Check if a host is up and scan for open ports, also skip host discovery.
```bash
#skips checking if the host is alive which may sometimes cause a false positive and stop the scan.
# skips checking if the host is alive. this may sometimes cause a false positive, stopping the scan.
$ nmap google.com -Pn
# Example output:
@ -2520,7 +2520,7 @@ $ nmap -A -T4 scanme.nmap.org
# -A to enable OS and version detection, script scanning, and traceroute; -T4 for faster execution
```
##### Look up website information (e.g. name server), searches for an object in a RFC 3912 database.
##### Look up website information (e.g. name server), searches for an object in a RFC 3912 database
```bash
whois google.com
```
@ -2731,11 +2731,11 @@ comm -23 fileA fileB
```bash
nl fileA
#or
# or
nl -nrz fileA
# add leading zeros
#or
# or
nl -w1 -s ' '
# making it simple, blank separate
```
@ -2870,7 +2870,7 @@ echo -e 'text here \c'
##### View first 50 characters of file
```bash
head -c 50 file
head -c 50 filename
```
##### Cut and get last column of a file
@ -2926,9 +2926,9 @@ echo 'hihi' >>filename
##### Working with json data
```bash
#install the useful jq package
#sudo apt-get install jq
#e.g. to get all the values of the 'url' key, simply pipe the json to the following jq command(you can use .[]. to select inner json, i.e jq '.[].url')
# Install the useful jq package
# sudo apt-get install jq
# e.g. to get all the values of the 'url' key, simply pipe the json to the following jq command(you can use .[]. to select inner json, i.e jq '.[].url')
cat file.json | jq '.url'
```
@ -3001,7 +3001,7 @@ while read a b; do yes $b |head -n $a ; done <test.txt
## Others
[[back to top](#handy-bash-one-liners)]
##### Describe the format and characteristics of image files.
##### Describe the format and characteristics of image files
```bash
identify myimage.png
#myimage.png PNG 1049x747 1049x747+0+0 8-bit sRGB 1.006MB 0.000u 0:00.000
@ -3124,7 +3124,7 @@ history -w
vi ~/.bash_history
history -r
#or
# or
history -d [line_number]
```