Commands by syntaxerror74

Commands by syntaxerror74 (2)

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List all symbolic links in current directory that matches regexp

If you want to search for all symlinks in current directory AND its subdirectories, make sure you omit the "-maxdepth 1" bit. Also, modify regextype as desired. I DO prefer to AVOID the use of extended regexp whenever possible, because this will usually only give correct results if you use GNU find. Hack a line containing ext-regexp into an HP-UX workstation, and you're in trouble.
This is sample output - yours may be different.
0

find . -maxdepth 1 -type l -regextype posix-basic -regex '.*what[ev]er?.*'

syntaxerror74 · 2015-06-06 16:22:25 9
get name of file that is currently playing in mplayer (if there)

grep -v '$/dev/\|pipe:\|socket:$' seemingly looks a bit complicated. This can, of course, be replaced by head -1. However, it is not sure whether the filename line will be first on all systems, so I chose the safer way by filtering out what is not needed here. Show Sample Output
This is sample output - yours may be different.
```
now playing: your fav artist - your fav track.mp3
now playing: your fav movie.mpeg
no track/video playing
```
0

media="$(basename "$(readlink /proc/$(pidof mplayer)/fd/* | grep -v '$/dev/\|pipe:\|socket:$')")" && ((test -n "$media" && echo "now playing: $media") || echo "no track/video playing")

syntaxerror74 · 2015-06-06 13:15:15 9

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Start a command on only one CPU core

This is useful if you have a program which doesn't work well with multicore CPUs. With taskset you can set its CPU affinity to run on only one core.

Install pip with Proxy

Installs pip packages defining a proxy

add the result of a command into vi

in command mode, navigate your cursor to the line where you want the command output to appear, and hit "!!". No need to enter edit mode or even type a ":" (colon).

Get a process's pid by supplying its name

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

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" }

Single use vnc-over-ssh connection

This command 1. SSH into a machine 2. Tunnels VNC port to your local computer ("-L 5900:localhost:5900") 3. Runs a single use vnc server ("x11vnc -safer -localhost -nopw -once -display :0") 4. Goes into the background ("-f") 5. Runs VNC viewer on the local computer connecting to the remote machine via the newly created SSH tunnel ("vinagre localhost:5900")

Redirect a filehandle from a currently running process.

This command uses the debugger to attach to a running process, and reassign a filehandle to a file. The two commands executed in gdb are p close(1) which closes STDOUT and p creat("/tmp/filename",0600) which creates a file and opens it for output. Since file handles are assigned sequentially, this command opens the file in place of STDOUT and once the process continues, new output to STDOUT will instead be written to our capture file.

Instant mirror from your laptop + webcam (fullscreen+grab)

This directly puts the "mirror" into fullscreen, and lets you take photos by pressing the 's' key. I bet appearance conscious people will have keyboard shortcut for this command by now.

Merge several pdf files into a single file

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