Skip to the relevant sections if needed.
/// 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 |
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); |
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. |
- Use
curl
to get the JSON response for the latest release - Use
grep
to find the line containing file URL - Use
cut
andtr
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 \" \
[ Update 2025-03-24: Commenting is disabled permanently. Previous comments are archived at web.archive.org. ]
Most of the terminal emulators auto-detect when a URL appears onscreen and allow to conveniently open them (e.g. via Ctrl+click or Cmd+click, or the right click menu).
It was, however, not possible until now for arbitrary text to point to URLs, just as on webpages.
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