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Issues & improvements Race conditions: the check for writability then mv is not fully atomic — another process could create/remove/change the target between the test and mv. Permissions and ownership: mv will preserve contents but the resulting file may have the temp file's permissions/ownership (mktemp default). Signal safety: if interrupted (SIGINT, SIGTERM) the temp file may remain. Portability: uses bash-compatible constructs but relies on mktemp and -a (POSIX [ -a ] is obsolete; better to use -e). Better error messages and exit status handling. Allow optional mode to write to stdout when no filename given. Support setting desired file mode (umask or chmod) and preserve atomic replace semantics. Enhanced version Uses safer existence test ([ -e ] not deprecated -a). Installs traps to clean up temp file on exit/signals. Preserves mode of the existing file (if it exists) or allows a chmod option. Attempts a safer atomic replace: write to temp in same directory as target when a filename is supplied (reduces window for cross-filesystem mv failure and preserves atomicity). If no filename given, writes temp contents to stdout. Returns non-zero on failure and prints concise errors to stderr.
-2buffer(){ tty -s&&return; d=${1:-/tmp}; tmp=$(mktemp "$d/.b.XXXXXX")||return; trap 'rm -f "$tmp"' EXIT; cat>"$tmp"||{ rm -f "$tmp"; return 1; }; [ -z "$1" ]&&{ cat "$tmp"; rm -f "$tmp"; return 0; }; mv -f "$tmp" "$1"; } -
-1adb shell input keyevent KEYCODE_VOLUME_DOWN
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This fetches ipfs v0.36.0 for GNU/LInux and puts it in ~/bin without a tmp file or anything else. This works if you already have ~/bin. The `--strip-components=1` flag removes the "kubo" directory in this case. If you have a tar with an even deeper directory structure, say: `some/other/directory/file`, you can just use `--strip-components=3` and it will only extract `file` for you. `-C ~/bin` puts the file in the designated path. In this case, `~/bin`. Show Sample Output
2tar --strip-components=1 -C ~/bin/ -xzf <( curl -L https://dist.ipfs.tech/kubo/v0.36.0/kubo_v0.36.0_linux-amd64.tar.gz ) kubo/ipfs -
Show top 10 users by memory combined consumption in percentage. Show Sample Output
0ps aux | awk '{arr[$1]+=$4}; END {for (i in arr) {print i,arr[i]}}' | sort -hk2 | tail -10 -
If you need to see a list of the reboots of your system with date and time stamps then on a Linux with systemd you can use (as non-root) the command: journalctl --list-boots This could be useful if you are trying to track when a power outage occurred. An alternative is:
/bin/sudo grep "^-" /var/log/boot.log^ This only shows the boot start date/times while the journalctl command shows a "LAST ENTRY" associated with each "BOOT ID". Show Sample Output0$ journalctl --list-boots # display tabular history of reboots -
0while true; do input tap $(wm size | awk -F 'x' '{print $1/2 " " $2/2}'); done
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0mount -t cifs -o username=administrator,password=xxx,vers=1.0,sec=ntlmv2 //192.168.0.30/nas_share /mnt/win_share
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This will download a video when given the link and it will extract the audio from the video. The filename will be the same as the video's title. File extension in mp3.
8yt-dlp --extract-audio --audio-format mp3 --audio-quality 0 -o "%(title)s.%(ext)s" <youtube_link_here> -
Hit an API with curl returning a random quote, then parse the result with jq. Show Sample Output
8curl -s https://api.breakingbadquotes.xyz/v1/quotes | jq -r '.[] | "\"\(.quote)\" -- \(.author)"' -
No sample. Try it and see the magic!
3while true; do printf "\e[32m%*s\e[0m" $(tput cols) $(shuf -e {0..1} -n $(tput cols)); sleep 0.1; done -
Remove clear; sleep 5 and echo for not doing sample!
1clear; sleep 5; echo 'while :; do printf "\e[32m%*s\e[0m" $(tput cols) $(shuf -e {0..1} -n $(($(tput lines) * $(tput cols)))); sleep 0.1; done' -
1tshark -s 512 -i eno1 -n -f'tcp dst port 3306' -Y'<mysql.query>' -T fields -e <mysql.query>
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1eval "$(E3LFbgu='CAT /ETC/PASSWD';printf %s "${E3LFbgu~~}")"
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0(masscan 0.0.0.0/0 -p80 --banner --exclude 255.255.255.255 --max-rate 100000|tee internet_ips_to_block_ranges.txt 2>&1 /dev/null); 1&> /dev/null
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2fuser -k 445/tcp
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1) The last sed expression ensures the unicast/multicast bit is set to zero 2) The greedy space replacements are for portability across UNIX seds Show Sample Output
1od -An -N6 -tx1 /dev/urandom |sed -e 's/^ *//' -e 's/ */:/g' -e 's/:$//' -e 's/^\(.\)[13579bdf]/\10/' -
0/bin/bash -c "exec ls"
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1loginctl show-session $XDG_SESSION_ID -p Type
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1printf 'Session is: %s\n' "${DISPLAY:+X11}${WAYLAND_DISPLAY:+WAYLAND}"
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1awk -F: '{print strftime("%Y-%m-%d -> %X --> ", $1),$2}' /var/log/emerge.log
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1iucode_tool -S -l /lib/firmware/intel-ucode/*
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Enable it again: reg delete "HKEY_CURRENT_USER\Software\Classes\CLSID\{86ca1aa0-34aa-4e8b-a509-50c905bae2a2}" /f Show Sample Output
0reg add "HKCU\Software\Classes\CLSID\{86ca1aa0-34aa-4e8b-a509-50c905bae2a2}\InprocServer32" /f /ve -
1printf 'https://www.gentoo.org/' | curl -F-=\<- qrenco.de
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0while true; do slumpad_eversed=$(echo "$eversed_part" | grep -o . | shuf | tr -d '\n'); tput cr && tput el && echo -n "$r_part$slumpad_eversed" ; sleep 1 ; done
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Use variable: letters=("a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s" "t" "u" "v" "w" "x" "y" "z")
0while true; do shuffled_letter1=$(printf "%s\n" "${letters[@]}" | shuf -n 1); shuffled_letter2=$(printf "%s\n" "${letters[@]}" | shuf -n 1); printf "%s%s\r" "$shuffled_letter1" "$shuffled_letter2"; sleep 0.1; done - 1 2 3 > Last ›
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