Commands by rjamestaylor (4)

  • Although Exim will purge frozen (undeliverable) messages over time, the command "exim -Mrm #id#" where #id# is a particular message ID will purge a message immediately. Being lazy, I don't want to type the command for each frozen message, so I wrote the one-liner to do it for me.


    -2
    for i in `mailq | awk '$6 ~ /^frozen$/ {print $3}'`; do exim -Mrm $i; done
    rjamestaylor · 2010-01-13 21:28:45 3
  • Show the maximum settings in effect for PHP at the command line. Show Sample Output


    -2
    php -i|grep -i max
    rjamestaylor · 2009-02-20 03:29:11 6
  • Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this: for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done Very useful for triage on unfamiliar servers! Show Sample Output


    2
    lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'
    rjamestaylor · 2009-02-19 16:11:54 5
  • Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc. Show Sample Output


    6
    links --dump 1 http://localhost/server-status|grep ^[0-9]|awk 'BEGIN {print "Seconds, PID, State, IP, Domain, TYPE, URL\n--"} $4 !~ /[GCRK_.]/ {print $6, $2, $4, $11, $12, $13 " " $14|"sort -n"}'
    rjamestaylor · 2009-02-19 13:06:44 11

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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" }

Let's make screen and ssh-agent friends
When you start screen as `ssh-agent screen`, agent will die after detatch. If you don't want to take care about files when stored agent's pid/socket/etc, you have to use this command.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Find the package that installed a command

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" }

Get the size of all the directories in current directory (Sorted Human Readable)
This allows the output to be sorted from largest to smallest in human readable format.

Remove spaces from filenames - through a whole directory tree.
An example of zsh glob qualifiers.

Recursively grep for string and format output for vi(m)
This is a big time saver for me. I often grep source code and need to edit the findings. A single highlight of the mouse and middle mouse click (in gnome terminal) and I'm editing the exact line I just found. The color highlighting helps interpret the data.

Unite pdf files
pdfunite is a part of the poppler-utils. poppler-utils package is only 150KB. The alternative - pdftk package is 14MB! Install poppler-utils if you need simple pdf operation commands like unite, separate, info, text/html conversions


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