Commands by anjo (1)

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Send a local file via email
Send it the easy way, with MIME and everything handled for you by an app that knows best.

Quick HTML image gallery from folder contents
Setting: You have a lot of jpg files in a directory. Maybe your public_html folder which is readable on the net because of Apache's mod_userdir. All those files from the current folder will be dropped into a file called gallery.html as image tags that can be viewed within a web browser locally or or over the Internet. Original: $find . -iname "*.jpg" -exec echo "" >> gallery.html \;

Find Duplicate Files (based on MD5 hash) -- For Mac OS X
This works on Mac OS X using the `md5` command instead of `md5sum`, which works similarly, but has a different output format. Note that this only prints the name of the duplicates, not the original file. This is handy because you can add `| xargs rm` to the end of the command to delete all the duplicates while leaving the original.

See OpenVZ Container id's of top 10 running processes by %cpu
This command will list the PID, VEID, and Name of the 10 highest cpu using processes on a openvz host. You must have vzpid installed.

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"

diff will usually only take one file from STDIN. This is a method to take the result of two streams and compare with diff. The example I use to compare two iTunes libraries but it is generally applicable.
diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.

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)

One-liner to generate Self-Signed SSL Certificate+Key without any annoying prompts or CSRs
Handy if you want to quickly generate a self-signed certificate. Also can be used in your automated scripts for generating quick-use certificates.

Find the package that installed a command

List all symbolic links in current directory
Many competing commands to do this, but since most people want a Long list with Human readable files sizes and want to see All files (including hidden (.*) files) this one wins on simplicity and usefulness. Plus grep is just as, if not more portable than sed or awk, and is more widely understood. :)


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