Locks

NSPR
About NSPR
NSPR API Reference
NSPR Build Instruction
NSPR Release Process
Introduction to NSPR
NSPR Types
Threads
1. Threading Types and Constants
2. Threading Functions
Process Initialization
Locks
1. Lock Type
2. Lock Functions
Condition Variables
1. Condition Variable Type
2. Condition Variable Functions
Monitors
1. Monitor Type
2. Monitor Functions
Cached Monitors
1. Cached Monitor Functions
I/O Types
I/O Functions
Network Addresses
1. Network Address Types and Constants
2. Network Address Functions
Atomic Operations
Interval Timing
1. Interval Time Type and Constants
2. Interval Functions
Date and Time
Memory Management Operations
1. Memory Allocation Functions
2. Memory Allocation Macros
String Operations
Floating Point Number to String Conversion
Linked Lists
1. Linked List Types
  1. PRCList
2. Linked List Macros
Dynamic Library Linking
Process Management and Interprocess Communication
1. Process Management Types and Constants
  1. PRProcess
  2. PRProcessAttr
2. Process Management Functions
  1. Setting the Attributes of a New Process
  2. Creating and Managing Processes
Logging
Named Shared Memory
1. Shared Memory Protocol
2. Named Shared Memory Functions
Anonymous Shared Memory
1. Anonymous Memory Protocol
2. Anonymous Shared Memory Functions
IPC Semaphores
1. IPC Semaphore Functions
Thread Pools
1. Thread Pool Types
2. Thread Pool Functions
Random Number Generator
1. Random Number Generator Function
Hash Tables
1. Hash Tables and Type Constants
2. Hash Table Functions
NSPR Error Handling
Contribute
2. The MDN Project

This chapter describes the NSPR API for creation and manipulation of a mutex of type PRLock.

In NSPR, a mutex of type PRLock controls locking, and associated condition variables communicate changes in state among threads. When a programmer associates a mutex with an arbitrary collection of data, the mutex provides a protective monitor around the data.

In general, a monitor is a conceptual entity composed of a mutex, one or more condition variables, and the monitored data. Monitors in this generic sense should not be confused with monitors used in Java programming. In addition to PRLock, NSPR provides another mutex type, PRMonitor, which is reentrant and can have only one associated condition variable. PRMonitor is intended for use with Java and reflects the Java approach to thread synchronization.

For an introduction to NSPR thread synchronization, including locks and condition variables, see Introduction to NSPR.

Lock Type

Lock Functions