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@jspahrsummers
jspahrsummers / GHRunLoopWatchdog.h
Created January 28, 2015 20:50
A class for logging excessive blocking on the main thread
/// Observes a run loop to detect any stalling or blocking that occurs.
///
/// This class is thread-safe.
@interface GHRunLoopWatchdog : NSObject
/// Initializes the receiver to watch the specified run loop, using a default
/// stalling threshold.
- (id)initWithRunLoop:(CFRunLoopRef)runLoop;
/// Initializes the receiver to detect when the specified run loop blocks for
@steipete
steipete / PSPDFEnvironment.m
Last active March 5, 2024 09:15
Example for DISPATCH_SOURCE_TYPE_MEMORYPRESSURE (Mac only, since 10.9) ... Since we share code between iOS and mac, I'm trying to be a good system citizen and reimplement the equivalent of UIApplicationDidReceiveMemoryWarningNotification on the Mac.
NSString *const PSPDFApplicationDidReceiveMemoryWarningNotification = @"PSPDFApplicationDidReceiveMemoryWarningNotification";
// Test with sudo memory_pressure -l critical. Don't forget to re-set afterwards!
__attribute__((constructor)) static void PSPDFInstallLowMemoryNotificationWarningMac(void) {
static dispatch_source_t source;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
source = dispatch_source_create(DISPATCH_SOURCE_TYPE_MEMORYPRESSURE, 0, DISPATCH_MEMORYPRESSURE_WARN|DISPATCH_MEMORYPRESSURE_CRITICAL, dispatch_get_main_queue());
dispatch_source_set_event_handler(source, ^{
dispatch_source_memorypressure_flags_t pressureLevel = dispatch_source_get_data(source);
@shacker
shacker / gist:87908e13c9ee6655ce90
Last active July 17, 2024 14:55
Using the Workday API with Python and the suds client library
import sys
from suds import client
from suds.wsse import Security, UsernameToken
from suds.sax.text import Raw
from suds.sudsobject import asdict
from suds import WebFault
'''
Given a Workday Employee_ID, returns the last name of that employee.
@steinwaywhw
steinwaywhw / One Liner to Download the Latest Release from Github Repo.md
Last active October 11, 2025 23:11
One Liner to Download the Latest Release from Github Repo
  • Use curl to get the JSON response for the latest release
  • Use grep to find the line containing file URL
  • Use cut and tr to extract the URL
  • Use wget to download it
curl -s https://api.github.com/repos/jgm/pandoc/releases/latest \
| grep "browser_download_url.*deb" \
| cut -d : -f 2,3 \
| tr -d \" \
@ldez
ldez / gmail-github-filters.md
Last active October 10, 2025 09:53
Gmail and GitHub - Filters

Gmail and GitHub

How to filter emails from GitHub in Gmail and flag them with labels.

The labels in this document are just examples.

Pull Request

Filter Label
@egmontkob
egmontkob / Hyperlinks_in_Terminal_Emulators.md
Last active October 14, 2025 16:24
Hyperlinks in Terminal Emulators
@romainl
romainl / redir.md
Last active September 11, 2025 23:26
Redirect the output of a Vim or external command into a scratch buffer

Redirect the output of a Vim or external command into a scratch buffer

Usage (any shell)

Show full output of command :hi in scratch window:

:Redir hi

Show full output of command :!ls -al in scratch window:

@tclementdev
tclementdev / libdispatch-efficiency-tips.md
Last active September 20, 2025 20:31
Making efficient use of the libdispatch (GCD)

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

  • You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

  • Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse