Commands using less (59)

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recursive reset file/dir perms
Good for fixing web permissions. You might also want to do something like this and skip files or directories that begin with a period: $ find public_html/stuff -not -name ".*" \( -type d -exec chmod 755 {} + -o -type f -exec chmod 644 {} + \) ...or include a special case for scripts: $ find public_html/stuff -type d -exec chmod 755 {} + -or -type f -name "*.pl" -exec chmod 755 {} + -or -exec chmod 644 {} +

Encrypted chat with netcat and openssl (one-liner)
client$ while true; do read -n30 ui; echo $ui |openssl enc -aes-256-ctr -a -k PaSSw ; done | nc localhost 8877 | while read so; do decoded_so=`echo "$so"| openssl enc -d -a -aes-256-ctr -k PaSSw`; echo -e "Incoming: $decoded_so"; done This will establish a simple encrypted chat with AES-256-CTR using netcat and openssl only. More info here

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

use xxd to create the wake on lan magicpacket and write to pcap file
just set macdst to the mac address of the system you wish to wake up, the macsrc is optional but helps use tcpreplay to broadcast or wireshark to view

Show running services (using systemctl)

Check a nfs mountpoint and force a remount if it does not reply after a given timeout.
Based on the execute with timeout command in this site. A more complex script: #!/bin/sh # This script will check the avaliability of a list of NFS mount point, # forcing a remount of those that do not respond in 5 seconds. # # It basically does this: # NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH) # TIMEOUT=5 SCRIPT_NAME=$(basename $0) for i in [email protected]; do echo "Checking $i..." if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2 echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2 umount -fl $i; echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2 mount $i; fi done

Recursively touch all files and subdirectories

Compare a remote file with a local file
A little messy, but functional. Requires vim >= 7.x.

Get Shellcode from ARM Binaries
Getting shellcode from ARM binaries - @OsandaMalith

When was your OS installed?
Show time and date when you installed your OS.

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