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Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Determine if a command is in your $PATH using POSIX
it is generally advised to avoid using which(1) whenever possible. which(1) is usually a csh(1) script, or sometimes a compiled binary. It's output is highly variable from operating system to operating system, so platform independent scripts could become quite complicated with the logic. On HP-UX 10.20, for example, it prints "no bash in /path /path /path ..."; on OpenBSD 4.1, it prints "bash: Command not found."; on Debian (3.1 through 5.0 at least) and SuSE, it prints nothing at all; on Red Hat 5.2, it prints "which: no bash in (/path:/path:...)"; on Red Hat 6.2, it writes the same message, but on standard error instead of standard output; and on Gentoo, it writes something on stderr. And given all these differences, it's still variable based on your shell. This is why POSIX is king. See http://mywiki.wooledge.org/BashFAQ/081 for more ways on avoiding which(1).

check open ports without netstat or lsof

List only directories, one per line
omit the 1 (one) if you don't need one-per-line

Using Git, stage all manually deleted files.
You'll probably want to pass in the -rf options if you have to delete a directory or something.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Viewing Top Processes according to cpu, mem, swap size, etc.
I've wanted this for a long time, finally just sat down and came up with it. This shows you the sorted output of ps in a pretty format perfect for cron or startup scripts. You can sort by changing the k -vsz to k -pmem for example to sort by memory instead. If you want a function, here's one from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html $ aa_top_ps(){ local T N=${1:-10};T=${2:-vsz}; ps wwo pid,user,group,vsize:8,size:8,sz:6,rss:6,pmem:7,pcpu:7,time:7,wchan,sched=,stat,flags,comm,args k -${T} -A|sed -u "/^ *PID/d;${N}q"; }

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" }

Clear terminal Screen
Probably the quickest / easiest way to clear the screen.

Diff 2 file struct - Useful for branch diff and jars diff(uncompressed)
This is usefull to diff 2 paths in branches of software, or in different versions of a same zip file. So you can get the real file diff.

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