Commands tagged tr (81)

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processes per user counter
awk is evil!

Limit the cpu usage of a process
Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: $ bc -l

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

dstat- this command is powerful one to monitor system activity . It has combined the power of vmstat,iostat,mpstat,df,free,sar .
As mentioned in the summery that it is a powerful command to monitor system activity in great way. It has got the power of vmstat,iostat,mpstat,df,free and sar.Instead of firing each single command separately ,one can fire one single command to get all the info at once.But there is a way to get the individual information too. Please see the man page . You can get it from here : http://dag.wieers.com/home-made/dstat/

ssh: change directory while connecting
Useful to create an alias that sends you right in the directory you want : alias server-etc="ssh -t server 'cd /etc && $SHELL'"

Target a specific column for pattern substitution
Awk replaces every instance of foo with bar in the 5th column only.

ssh -A [email protected]
the -A argument forwards your ssh private keys to the host you're going to. Useful in some scenarios where you have to hop to one server, and then login to another using a private key.

list block devices
Shows all block devices in a tree with descruptions of what they are.

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

List all symbolic links in current directory that matches regexp
Perl alternative to list symlinks with a clumsy regexp filter: place the regex instead of he example 'libxml' and end it with a wildchar to see the results (previous cd on dir). Is it possible change the '-l' test for '-d' and it will search for directories. [Same applies for -x and -X. See $(perldoc -f -x) for more tests]. I use it quite often when dealing with shared libraries...


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