Cli on traviscj/blog

macos log command

Thu, 23 May 2019 00:00:00 +0000

My work laptop has been randomly shutting itself off. I came across this stackoverflow post, it said to run

log show \
  --predicate 'eventMessage contains "Previous shutdown cause"' \
  --last 24h

which, for me, returns

risksys  ➜ log show --predicate 'eventMessage contains "Previous shutdown cause"' --last 24h
Filtering the log data using "composedMessage CONTAINS "Previous shutdown cause""
Skipping info and debug messages, pass --info and/or --debug to include.
Timestamp                       Thread     Type        Activity             PID    TTL
2019-05-23 11:29:01.874486-0700 0xaf       Default     0x0                  0      0    kernel: (AppleSMC) Previous shutdown cause: -128
2019-05-23 11:44:49.786722-0700 0xaf       Default     0x0                  0      0    kernel: (AppleSMC) Previous shutdown cause: -128
--------------------------------------------------------------------------------------------------------------------
Log      - Default:          2, Info:                0, Debug:             0, Error:          0, Fault:          0
Activity - Create:           0, Transition:          0, Actions:           0

This, combined with these MacOS Shutdown Causes paints a pretty bleak picture: I’ve got RAM issues :-(

smart arguments

Thu, 21 Feb 2019 00:00:00 +0000

It’s easy to love the terseness one can get out of a command-line tool with a “pass by order” convention. For example, maybe I run something like

deploy myapp sea2 production

to deploy an application called myapp to the second production datacenter near Seattle. This works great, except now I need to remember the order of arguments is: deploy [app] [datacenter] [environment].

The typical solve for this problem is introducing named arguments, so you’d end up with

watching progress in mysql

Fri, 04 Jan 2019 00:00:00 +0000

Pretty frequently at work, I end up polling a database with some command like

SELECT MAX(id) FROM my_tbl;
SELECT MAX(id) FROM my_tbl;
SELECT MAX(id) FROM my_tbl;
SELECT MAX(id) FROM my_tbl;
-- .... ad nauseam ....

I’ve eventually noticed a few patterns I use pretty consistently:

estimate ETA by including `NOW()`/`UNIX_TIMESTAMP()`

Generally, the point of hovering over the table is to get an estimate of when it will finish/catch up/whatever. For that, you generally want to include a timestamp in the query output, so when you come back a while later, you can know exactly how much time has elapsed. I might transform the above query into

sfpark api

Tue, 24 Apr 2018 16:29:39 +0000

I recently came to learn of the SFpark API, which lets one make queries like:

LAT=37.787702
LONG=-122.407796
curl "http://api.sfpark.org/sfpark/rest/availabilityservice?lat=${LAT}&long=${LONG}&radius=0.25&uom=mile&response=json" | pbcopy
pbpaste | jq '.AVL[] | select (.TYPE | contains("OFF"))'

and get a response including records like:

{
  "TYPE": "OFF",
  "OSPID": "950",
  "NAME": "Union Square Garage",
  "DESC": "333 Post Street",
  "INTER": "Geary between Stockton & Powell",
  "TEL": "(415) 397-0631",
  "OPHRS": {
    "OPS": {
      "FROM": "7 Days/Wk",
      "BEG": "24 Hrs/Day"
    }
  },
  "OCC": "381",
  "OPER": "670",
  "PTS": "1",
  "LOC": "-122.407447946,37.7876789151"
}

Pretty cool!

osquery

Fri, 12 Jan 2018 08:43:17 +0000

I’ve known about [osquery][] for a while, but recently spent some time digging around in it. [osquery]: https://osquery.io The basic idea is to provide a consistent SQL interface to a bunch of system data, instead of learning idiosyncrasies of individual commands (which themselves vary across operating systems). My hacker buddy Sharvil has worked on osquery a fair bit and explained to me a couple years ago that it actually uses [sqlite][]’s [virtual table functionality][vtab] to provide the interface – it’s a fascinating and brilliant project! [sqlite]: https://sqlite.org/ [vtab]: https://sqlite.org/vtab.html

.sqliterc

Fri, 31 Mar 2017 00:00:00 +0000

I came across Better output from sqlite3 command line. His .sqliterc file did not work for me, but the simpler

.mode "column"
.headers on

did work nicely.

I also found out that brew install sqlite3 does not install the sqlite3 binary to $PATH, which stinks.

The sqlite3 environment is still much less pleasant than the mysql cli. A few things on my wishlist:

tab completion of tables, fields, keywords, and functions.
nicer .schema output – I’ve just gotten really used to reading them in mysql output

It sounds like maybe apsw can be something useful? Or maybe Navicat? (but that’s expensive)

Useful homebrew formula

Thu, 01 Dec 2016 00:00:00 +0000

Last week I was telling Paul about things I have brew installed on my work laptop. I pulled a full list as I was doing some upgrades and stuff this morning.

Glancing over it a bit, here are some of my favorites/most usefuls:

autojump for a usage-adjusting cd – given a partial string it just goes to the most-used directory with that prefix. I have autojump aliased to j to shorten it up even more.
colordiff to make diffs/grep/etc nicer to look at in the terminal.
coreutils/dateutils is nice because it installs the GNU versions of a lot of standard linux commands like du and ls and date that work a bit strange/differently on OSX.
jq is amazing — lets you query JSON objects.
ledger to manage bank balances in plain text.
newsbeuter to subscribe to RSS feeds.
osquery lets you do SQL-like queries to find out about the system it’s running on (sharvil did a bunch of work on it, actually…)
terminal-notifier to pop up notifications from terminal/cron jobs.
tmux to have long-running terminal windows without having terminal windows open.
watch instead of “some command”+uparrow+enter+uparrow+enter+….
wget as shorthand for “curl http://xyz/tuv.json > tuv.json” (old habits…),
youtube-dl for downloading youtube videos.

debugging internet

Tue, 28 Oct 2014 00:00:00 +0000

My standard plan for debugging internet connections:

Can we reach stuff from some other device?

Usually, connection problems are something like “My iPad isn’t working,” which is caused by a flash of light in the sky, like when Swamp gas from a weather balloon gets trapped in a thermal pocket and reflects the light from Venus."

So try something other than your iPad on your WiFi to isolate whether it is a WiFi network problem or a “iPad"problem.

mnemonicode-0.73

Thu, 10 Jul 2014 00:00:00 +0000

I found a really cool tool called mnemonicode.

It basically encodes an arbitrary string into some easily-sayable and understandble phrases:

Traviss-MacBook-Pro% echo "hello world" | ./mnencode
 Wordlist ver 0.7
square angel stone. blitz pacific tango. zebra shave basic
Traviss-MacBook-Pro% echo square angel stone. blitz pacific tango. zebra shave basic | ./mndecode
hello world

piping for fun and profit

Thu, 29 May 2014 00:00:00 +0000

I recently discovered something pretty cool: groovy, and in particular groovysh. It lets you do cool stuff like run JVM functions:

➜  ~  groovysh
Groovy Shell (2.3.3, JVM: 1.8.0)
Type ':help' or ':h' for help.
-------------------------------------------------------------------------------
groovy:000> new Random().nextInt()
===> 909782845

But the sad part is that it seems pretty slow on my machine:

➜  ~  time (echo :q | groovysh)
Groovy Shell (2.3.3, JVM: 1.8.0)
Type ':help' or ':h' for help.
-------------------------------------------------------------------------------
groovy:000> :q
( echo :q | groovysh; )  16.56s user 0.31s system 201% cpu 8.384 total

That’s more than 8 seconds just to start up and shut down a prompt that I might just run one command in!

Numerical Development on OSX (in the Command Line)

Mon, 19 Aug 2013 00:00:00 +0000

I’ve been working on C implementations of my research projects, which can of course be a perilous project. I’ve found some tools that make it hugely, hugely better.

Homebrew

You can’t do a list like this without mentioning homebrew. You want homebrew instead of MacPorts or Fink or bailing twine and chewing gum or whatever else you were thinking about using. Just do it: You can find the homepage at brew.sh or just install with:

ZSH and scp/rsync globbing

Tue, 25 May 2010 00:00:00 +0000

I finally got annoyed at typing

tjohnson> scp tcj:*txt .
zsh: no matches found: tcj:*txt

I’d always fixed this by the up-CTRL-A-over-over-over-over-quote-CTRL-E-over-over-quote method, ie

tjohnson> scp "tcj:*txt" .

but the more proper and less annoying version is

tjohnson> scp tcj:\*txt .

However, in the spirit of inspired overkill, there are a couple other options. You can define some new aliases with

alias scp='noglob scp'

but that hardly counts as overkill, so instead I edited my .zshrc to include

Minor OS X Shell Shortcomings

Sun, 19 Oct 2008 00:00:00 +0000

In spite of the fact that a lot of people seem to loathe the colorized ls functionality, I sortof grew up on it(so to speak). OS X, by default, does not have this functionality(well, at least, GNU’s –color option never works). I figured the quick and easy way to solve this was to install coreutils, but I found another option. It appears OSX included a version of ls that works with ls -G. The coreutils one is (by it’s virtue as a GNU tool) probably more feature-driven, but realiasing it as