Commands by clockworkavian (4)

  • This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution Show Sample Output


    23
    true && { echo success;} || { echo failed; }
    clockworkavian · 2009-04-02 01:49:25 3
  • Not so much handy by itself, but very nice in shell scripts. This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like: "one" "two" "three" "four" "etc" For those who prefer bash expansion over gratuitious typing: whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} ) Things to note: The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time. If the status is 1, it will be selected by default. anything else, will be deselected. Show Sample Output


    6
    whiptail --checklist "Simple checkbox menu" 11 35 5 tag item status repeat tags 1
    clockworkavian · 2009-03-30 12:21:48 4
  • This function runs a program in the background, and logs all output to an automatically created logfile. That way, you can still get at the output without it clogging up your terminal. Tip: Throw fork() and this: for prog in firefox kate konqueror ;do alias $prog="fork $prog";done into your bashrc, so that they'll automatically run out of the way. Show Sample Output


    1
    function fork () { tf=$(tempfile -d /tmp -p $1.);echo -n "$tf "; $@ &>$tf& }
    clockworkavian · 2009-03-25 23:33:54 3
  • Depending on the network setup, you may not get the hostname. Show Sample Output


    4
    nmap 192.168.0-1.0-255 -sP
    clockworkavian · 2009-03-23 22:19:05 5

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Install pip with Proxy
Installs pip packages defining a proxy

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

list files recursively by size

find files in a date range
Find files in a specific date range - in this case, the first half of last year. -newermt = modification time of the file is more recent than this date GNU find allows any date specfication that GNU date would accept, e.g. $ find . -type f -newermt "3 years ago" ! -newermt "2 years ago" or $ find . -type f -newermt "last monday"

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Twitter update from terminal (pok3's snipts ?)
Found it on snipt, pok3, is it yours? I put my user = m33600, the password and the status was my robot message: Settima robot message: ALARM ZONE 3 (sent via command line). Now bots may have their identity on twitter...

grep for minus (-) sign
Use flag "--" to stop switch parsing

ps with parent/child process tree
Shows a tree view of parent to child processes in the output of ps (linux). Similar output can be achieved with pstree (also linux) or ptree (Solaris).

Embed next line on the end of current line using sed
N: On the current line, sed will display it on pattern space, plus a \n (new line); but s/\n//: Will get rid of new line displayed on pattern space, joining the current line's end with the start of the next line Useful in scripts.


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