Commands by osvaldofilho (4)

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Print Memory Utilization Percentage For a specific process and it's children
Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

Add thousand separator with sed, in a file or within pipe
Does not necessarily require a file to process, it can be used in a pipe as well: $ cat filename | sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta' I don't remember where I copy/pasted this from, I wish I credited the original author

cat ~/.ssh/id_rsa.pub | ssh user@site.com "cat - >> ~/.ssh/authorized_keys"
You'll want to use this for passwordless logins. Same as ssh-copy-id, if you don't have it on your system.

List your MACs address
The output of ifconfig is localized, using it will fail in non-English environment. "ip" command in iproute2 provides a consistent output and thus is more robust

give a binary the ability to open ports below 1024 as non root user
Binding a server to privileged port on Linux w/o running as root This is applicable to any service using privileged ports (< 1024), for instance to run a HTTP server on port 80 or a LDAP directory server on port 389 for example.

Read funny developer comments in the Linux source tree
These are way better than fortune(6).

List programs with open ports and connections
I prefer to use this and not the -n variety, so I get DNS-resolved hostnames. Nice when I'm trying to figure out who's got that port open.

nmap port scanning
TCP Connect scanning for localhost and network 192.168.0.0/24

Block all FaceBook traffic

Rapidly invoke an editor to write a long, complex, or tricky command
Allows you to edit your command using your chosen editor. Works in bash with "set -o vi".

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