Where is pthread library

How are we doing? Please help us improve Stack Overflow. Take our short survey. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 10 years, 8 months ago. Active 4 years, 6 months ago. Viewed 52k times. In which directory does the libpthread library reside on a Linux system?

Improve this question. Bruce Becker 1 1 gold badge 6 6 silver badges 23 23 bronze badges. Dew Dew 2, 5 5 gold badges 15 15 silver badges 7 7 bronze badges. Hi - your question refers to a generic "Linux system" - this is a bit too vague to answer clearly. EMCC's -pthread option is not compatible with standalone mode, we need to pass -mbulk-memory -matomics to the compiler and --shared-memory,--no-check-features to linker manually.

You can build the wasm module into AoT module with pthread support, please pass option --enable-multi-thread to wamrc:. Currently WAMR disables pthread library by default. Here is also a sample to show how wasm-apps use pthread APIs to create threads, and how to build it with cmake.

You can build this sample and have a try:. The compiler may use some spaces in the linear memory as an auxiliary stack. The default value of N is 4, which means you can create 4 threads at most. This value can be changed by an option if you are using product-mini:.

Reference to an invalid key returns an error. This function does not invoke any of the destructors. The existing binding must be freed, otherwise a memory leak can occur. Example 2—2 shows an excerpt from a multithreaded program. This code is executed by any number of threads, but the code has references to two global variables, errno and mywindow. These global values really should be references to items private to each thread. References to errno should get the system error code from the routine called by this thread, not by some other thread.

Including the header file errno. The mywindow variable refers to a stdio stream that is connected to a window that is private to the referring thread. So, as with errno , references to mywindow by one thread should refer to a different storage location than references to mywindow by other threads.

Ultimately, the reference is to a different window. The only difference here is that the system takes care of errno , but the programmer must handle references for mywindow. The next example shows how the references to mywindow work. These variables are thread-specific data. References to mywindow behave as if direct references were made to data private to the thread. Example 2—4 shows how to set up the reference. This key is used to identify the thread-specific class of data.

The second argument is a destructor function that is used to deallocate a thread's instance of this thread-specific data item once the thread terminates. The next step is to allocate the storage for the caller's instance of this thread-specific data item.

When either tid1 or tid2 is an invalid thread identification number, the result is unpredictable. If no such threads are ready to run, the calling thread continues to run.

Otherwise, -1 is returned and errno is set to indicate the error condition. The caller does not have the appropriate permission to set either the scheduling parameters or the scheduling policy of the specified thread. When the following condition occurs, the function fails and returns the corresponding value. The caller does not have the appropriate permission to set the scheduling priority of the specified thread. The sig argument must be from the list that is given in signal.

When sig is zero, error checking is performed but no signal is actually sent. This error checking can be used to check the validity of tid. Add new to the current signal mask, where new indicates the set of signals to block. Delete new from the current signal mask, where new indicates the set of signals to unblock. Replace the current signal mask with new , where new indicates the new signal mask.

When the value of new is NULL , the value of how is not significant. The signal mask of the thread is unchanged. To inquire about currently blocked signals, assign a NULL value to the new argument. The old variable points to the space where the previous signal mask is stored, unless old is NULL.

All thread-specific data bindings are released. Otherwise, status is ignored. The thread's ID can be reclaimed immediately. The calling thread terminates with its exit status set to the contents of status. By returning from its first outermost procedure, the threads start routine.

The result of the join is that the joining thread picks up the exit status of the terminated thread and the terminated thread vanishes. An important special case arises when the initial thread, calling main , returns from calling main or calls exit. This action causes the entire process to be terminated, along with all its threads.

So, take care to ensure that the initial thread does not return from main prematurely. The other threads in the process, as well as the process, continue to exist. The process terminates when all threads terminate. Cancellation allows a thread to request the termination of any other thread in the process.