Commands by pooderbill (4)

  • Useful for finding newly added lines to a file, tail + can be used to show only the lines starting at some offset. A syslog scanner would look at the file for the first time, then record the end_of_file record number using wc -l. Later (hours, days), scan only at the lines that were added since the last scan. Show Sample Output


    1
    tail +### MYFILE
    pooderbill · 2015-04-23 11:49:15 4
  • view is the command: vi -r which opens a file in read-only mode. The + character jumps to the bottom of the logfile where the most relevant information starts. Other aliases can be created for commonly viewed logfiles. Show Sample Output


    -1
    view + LOGFILE
    pooderbill · 2015-04-21 11:23:01 4
  • ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line. Show Sample Output


    14
    ps -fC PROCESSNAME
    pooderbill · 2015-04-20 13:09:44 7
  • The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: noc /etc/hosts or grep server /etc/hosts | noc Change to nawk depending awk versions. Show Sample Output


    1
    alias noc="awk 'NF && ! /^[[:space:]]*#/'"
    pooderbill · 2014-09-07 00:50:57 60

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Simple way to envoke a secure vnc session through ssh enabled router.
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list block devices
Shows all block devices in a tree with descruptions of what they are.

Run a file system check on your next boot.
The empty file /forcefsck causes the file system check fsck to be run next time you boot up, after which it will be removed. This works too: $sudo >/forcefsck

Create higher quality gif from videos
I had to compress it a bit to meet the 255 limit. See sample for full command (274) usage: ffgif foo.ext Supports 3 arguments (optional) ffgif filename seek_time time_duration scale ffgif foo 10 5 320 will seek 10 seconds in, convert for 5 seconds at a 320 scale. Default will convert whole video to gif at 320 scale. Inspiration - http://superuser.com/questions/556029/how-do-i-convert-a-video-to-gif-using-ffmpeg-with-reasonable-quality/556031#556031

SHA256 signature sum check of file
get the SHA256 sum signatur for a file

monitor network traffic and throughput in real time
see http://iptraf.seul.org/ for all kinds of documentation and screenshots

Twitpic upload and Tweet

Fibonacci numbers with awk
recursive version, "pure" AWK

Optimal way of deleting huge numbers of files

Determine what version of bind is running on a dns server.
Due to the recent dynamic update vulnerability with bind, I was forced to dig a little deeper into dig...


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