Awesome Command Line

Remove PDF Watermark

Uncompress original pdf file to text file.

pdftk original.pdf output uncompressed.pdf uncompress
replace watermark strings to empty.

sed -i "s/watermarktextstring//g" uncompressed.pdf
Compress the edited text file back to pdf file.

pdftk uncompressed.pdf output fixed.pdf compress

Print Selected Columns of a CSV file

Print the 1st,3rd,5th columns

awk -F ',' '{print $1,$3,$5}' input.csv
Add a header before print

awk -F ',' 'BEGIN {print "index,col1,col2"} {print $1,$3,$5}' input.csv
Use comma to seperate output, OFS for "output field seperator"

awk -F ',' '{OFS=","}{print $1,$3,$5}' input.csv
Change print to printf

awk -F ',' 'BEGIN {print "index,col1,col2"} {printf("%s,%s,%s\n",$1,$3,$5}' input.csv

Generate a Random Password in Linux Terminal

date +%s | sha256sum | base64 | head -c 32 ; echo

SSH Asks for `password` When `authorized_keys` is Corrected Configured (with public keys)

Make sure the ownerships of user ufo are:
700 for /home/ufo
700 for /home/ufo/.ssh
600 for /home/ufo/.ssh/authorized_keys

Conda Configuration

Put ~/Anaconda3/condabin in system search path
Run conda config --set auto_activate_base true to activate base env when terminal starts (doesn't work for windows dos somehow)

Get Bandwidth of Network Interface

DOS wmic NIC where NetEnabled=true get Name, Speed ref
POWERSHELL Get-NetAdapter | where Status -eq "Up" | select InterfaceDescription, LinkSpeed ref
BASH sudo ethtool <interface> | grep Speed ref or cat /sys/class/net/<interface>/speed ref

Prepare a Start-up Script for Windows DOS Terminal (similar as ~/.bashrc in linux) ref

Edit the "%"USERPROFILE"%\init.cmd" script (script location could be anywhere) and put in commands such as activate for conda environment.
Run reg add "HKCU\Software\Microsoft\Command Processor" /v AutoRun ^ /t REG_EXPAND_SZ /d "%"USERPROFILE"%\init.cmd" /f
To remove the start-up operation, run reg delete "HKCU\Software\Microsoft\Command Processor" /v AutoRun

Mount Remote Drive

mount sudo sshfs -o allow_other username@serveIP:remote_folder local_mount_point
unmount sudo fusermount -u local_mount_point