c - Is getaddrinfo_a thread safe? -


i want use getaddrinfo_a function. method thread safe? in man page example given uses global list resolving hostnames. if manipulate list in user space safe? pseudo-code follows:

static struct gaicb **reqs =null; // global list of hostname resolve.  addtolist() {    ret =       getaddrinfo_a(          gai_nowait,          &reqs[nreqs_base],           nreqs - nreqs_base,          null ); // enque hostname queue. }  //another thread  method dequeu_list( int ) {    struct gaicb * result = reqs[i] ;    reqs[i] = null; }

yes, see in source code:

... int getaddrinfo_a (int mode, struct gaicb *list[], int ent, struct sigevent *sig) { ...   no acess list ...   /* request mutex.  */   pthread_mutex_lock (&__gai_requests_mutex);    /* can enqueue requests.  since acquired      mutex enqueue function need not this.  */   (cnt = 0; cnt < ent; ++cnt)     if (list[cnt] != null)       { ...

it acquires mutex before accessing list.

anyway it's similar getaddrinfo required thread-safe:

the freeaddrinfo() , getaddrinfo() functions shall thread-safe.


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