tss_set

Header: <threads.h>

Sets the value of the thread-specific storage identified by tss_id for the current thread to val. Different threads may set different values to the same key.

# Declarations

int tss_set( tss_t tss_id, void *val );

(since C11)

# Parameters

• tss_id: thread-specific storage key, obtained from tss_create and not deleted by tss_delete
• val: value to set thread-specific storage to

# Return value

thrd_success if successful, thrd_error otherwise.

# Notes

The POSIX equivalent of this function is pthread_setspecific.

Typically TSS is used to store pointers to blocks of dynamically allocated memory that have been reserved for use by the calling thread.

tss_set may be called in the TSS destructor. If the destructor exits with non-NULL value in the TSS storage, it will be retried by thrd_exit up to TSS_DTOR_ITERATIONS times, after which the storage will be lost.

# Example

int thread_func(void *arg) {
    tss_t key;
    if (thrd_success == tss_create(&key, free)) {
        tss_set(key, malloc(4)); // stores a pointer on TSS
        // ...
    }
} // calls free() for the pointer stored on TSS

# See also

• tss_get