Commands by bartonski (45)

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Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Prepend a text to a file.
The original command is great, but I often want to prepend to every line.

Optimal way of deleting huge numbers of files
This command works by rsyncing the target directory (containing the files you want to delete) with an empty directory. The '--delete' switch instructs rsync to remove files that are not present in the source directory. Since there are no files there, all the files will be deleted. I'm not clear on why it's faster than 'find -delete', but it is. Benchmarks here: https://web.archive.org/web/20130929001850/http://linuxnote.net/jianingy/en/linux/a-fast-way-to-remove-huge-number-of-files.html

Get the SAN (subjectAltName) of a site's certificate.
Based on http://stackoverflow.com/questions/13127352/checking-alternative-names-for-a-san-ssl-cert Replace "facebook.com" with the desired hostname.

currently mounted filesystems in nice layout
since fuse mounts do not appear in /etc/mtab (fuse can't write there, dunno if it would if it could) this is propably a better way.

Freshening up RKhunter
Not everyone reads manpages. Aliasing this command will help with the task of doing audits with RKhunter. It will check for the latest version, update the definitions and then run a check on the system. Hint: alias that in your .bashrc to make life for your fingers easier.

Find top 10 largest files in /var directory (subdirectories and hidden files included )
Should work even when very large files exist.

Display 16 largest installed RPMs in size order, largest first
Interesting to see which packages are larger than the kernel package. Useful to understand which RPMs might be candidates to remove if drive space is restricted.

Get Hardware UUID in Mac OS X
Formats the output from `ioreg` into XML, then parses the XML with `xmllint`'s xpath feature.

Download an entire website
-p parameter tells wget to include all files, including images. -e robots=off you don't want wget to obey by the robots.txt file -U mozilla as your browsers identity. --random-wait to let wget chose a random number of seconds to wait, avoid get into black list. Other Useful wget Parameters: --limit-rate=20k limits the rate at which it downloads files. -b continues wget after logging out. -o $HOME/wget_log.txt logs the output


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