This past week of work had me stretching my piping-ninja skills to the limits. In the past 4 days, I have created a oneliner that invoked xargs 3 times in a series of piped expressions, a oneliner that had xargs calling xargs, a oneliner that was well over 1000 characters and invoked sed, xargs, grep, perl, awk, xpathtool and others, sometimes twice, and several other ninja-like uses of filter-fu involving unix pipes. It's been a fun week for oneliners.

So, I thought I might spend the next 7 days covering some of the tools I find myself working with almost every day. I hope to cover all the ways I use a given tool, when it should be used over any alternatives, things to look up in the manpage, etc.

I'll try to cover more than one tool per day, because some tools can be batched together because there isn't much to day other than "this is useful for foo, bar, anz baz".

Tentative, incomplete list:

data sources

cat, GET, echo, nc (netcat), shell command substitution

filters

cut, grep, paste, sed, sort, tr, uniq, wc

magical

xargs, sh, awk, perl (for oneliners)

Here's a sneak peek at what you might learn:

'sort' can sort lines, right? But how do you sort words on the same line?

% echo "one two three four five" \
  | xargs -n1 | sort | xargs
five four one three two

Some of you might notice that the xargs(1) invocations can be replaced with tr(1). Yes. I use xargs(1) because it's less typing and handles many case tr(1) won't. This is not to say tr(1) doesn't have it's wonderful uses. More on that later this week ;)

If you have suggestions, let me know.