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@phette23
phette23 / current-dir-in-iterm-tab-title.sh
Last active March 31, 2025 14:56
Set the iTerm tab title to the current directory, not full path.
# put this in your .bash_profile
if [ $ITERM_SESSION_ID ]; then
export PROMPT_COMMAND='echo -ne "\033];${PWD##*/}\007"; ':"$PROMPT_COMMAND";
fi
# Piece-by-Piece Explanation:
# the if condition makes sure we only screw with $PROMPT_COMMAND if we're in an iTerm environment
# iTerm happens to give each session a unique $ITERM_SESSION_ID we can use, $ITERM_PROFILE is an option too
# the $PROMPT_COMMAND environment variable is executed every time a command is run
# see: ss64.com/bash/syntax-prompt.html
@shawnbutts
shawnbutts / bytesto.py
Created October 17, 2012 17:33
bytes to to mb, gb, etc in python
def bytesto(bytes, to, bsize=1024):
"""convert bytes to megabytes, etc.
sample code:
print('mb= ' + str(bytesto(314575262000000, 'm')))
sample output:
mb= 300002347.946
"""
a = {'k' : 1, 'm': 2, 'g' : 3, 't' : 4, 'p' : 5, 'e' : 6 }
@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = [email protected]:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

@jboner
jboner / latency.txt
Last active May 10, 2025 11:02
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD

tmux cheatsheet

As configured in my dotfiles.

start new:

tmux

start new with session name:

@wycats
wycats / gist:1627976
Created January 17, 2012 18:26
How to debug dynamic loading
export DYLD_PRINT_OPTS="1"
export DYLD_PRINT_ENV="1"
export DYLD_PRINT_LIBRARIES="1"
export DYLD_PRINT_LIBRARIES_POST_LAUNCH="1"
export DYLD_PRINT_APIS="1"
export DYLD_PRINT_BINDINGS="1"
export DYLD_PRINT_INITIALIZERS="1"
export DYLD_PRINT_REBASINGS="1"
export DYLD_PRINT_SEGMENTS="1"
export DYLD_PRINT_STATISTICS="1"