Commands using head (314)

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Mount a VMware virtual disk (.vmdk) file on a Linux box
Assumes XP/2000/2003. For Server 2008+ try offset=105,906,176 You can find this number in the System Information utility under Partition Starting Offset. UEFI based boxes you want partition 2 since the first is just the boot files (and FAT). This works with (storage side) snapshots which is handy for single file restores on NFS mounted VMware systems

[vim] Clear trailing whitespace in file
% acts on every line in the file. \s matches spaces. \+ matches one or more occurrences of what's right behind it. Character '$' matches end-of-line.

List NYC startups that are hiring

Shell function to exit script with error in exit status and print optional message to stderr
USAGE: die ERRNUM [MESSAGE]

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

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"

using tee to echo to a system file with sudo privileges
We sometimes need to change kernel parameters by echoing the file . This needs root privilege and if we do it using sudo like this , it fails $ sudo echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor -bash: /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor: Permission denied We can achieve this with the tee command by just doing sudo without logging as root user http://www.zaman4linux.in/2010/09/using-tee-to-echo-to-system-file-with.html

Print compile time in seconds package by package (Gentoo Distros)

Capture video of a linux desktop

show where symlinks are pointing
displays the output of ls -l without the rest of the crud. pretty simple but useful.


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