objective c usleep

The Usleep () function delays code execution for several microseconds. The unpack () function unpack the data from a binary string. The Uniqid () function generates a unique ID based on the current time in microseconds. The Time_sleep_until () function delays code execution until the specified time. The Time_nanosleep () function delays code execution for several seconds and nanoseconds. The sleep () function delays code execution for several seconds.

In Android, latency functions are divided into user space and kernel space: Kernel space # Include Udelay (int n ); Mdelay (INT n )); Ndelay (INT n )); These functions will lead to an endless cycle of CPU and lead to a busy wait of CPU. Usleep (int n ); Msleep (INT n )); Nsleep (INT n )); The difference between the first group and the second group of latency functions is that the first group of latency is a busy wait, and the process cannot be sched

. to create a cookie, your code uses the following entry: SetCookie ("user", "Emmett Dulaney", time () + 1800 ); which of the following is the best to use to see the value "Emmett Dulaney "? A. $ userB. $ COOKIE [user]C. $ _ COOKIE [user]D. $ COOKIE_user 28. Which of the following shocould be used to combine two or more existing arrays? A. array_add ()B. array_merge ()C. array_join ()D. array_combine () 29. What function is used to determine whether a session has been started for the current use

This script is a Chatterserver service control script that can control Chatterserver start, stop, reboot, and Status View through service commands, as if MySQL had/etc/init.d/mysql or/etc/init.d/ Like Mysqld, just this Chatterserver service control script is more difficult to write, and some information is more complex to capture and judge, because it is mainly related to the operation of Chatterserver and some of the things that happen during startup, This is well-marked in the script's comment

Example: Using two sub-processes to output in descending order from 50int g_num=50;Evenvoid *threadeven (void *lparam){while (g_num>0){if (! ( G_NUM1)){printf ("even:%d\n", g_num);}g_num--;Usleep (1);}return NULL;}Oddvoid *threadodd (void *lparam){while (g_num>0){if (g_num1){printf ("odd:%d\n", g_num);}g_num--;Usleep (1);}return NULL;}void Testmutex (){pthread_t thread1,thread2;int nret1=pthread_create (thr

Sleep function in C Language Sleep function: Function: the execution is suspended for a period of time. Usage: unsigned sleep (unsigned seconds ); Note: Use the header file # include In VC, the first English character in Sleep is "S" in uppercase. in linux, do not use uppercase letters. In Standard C, do not use sleep. In short, VC uses Sleep, use sleep for other purposes In VC, Sleep () is measured in milliseconds. Therefore, if you want to keep the function for 1 second, it should be Sleep (1

generate unique IDs are common, such as temporary cache file names, temporary variables, temporary security codes, and so on, and the uniqid () function generates a unique ID based on the current time in microseconds. Unique ID is very reliable due to the generation of a unique ID associated with microsecond time 2. PHP common functions (1) Introduction: In the daily development, most novice is very puzzled, so many PHP built-in function how to remember, in fact, you just know that there is th

actually does allow you to turn on and off the canonical mode. Okay, let see how it apply to work? 0102030405060708091011121314151617181920212223242526 int main(){char c;int i=0;nonblock(NB_ENABLE);while(!i){usleep(1);i=kbhit();if (i!=0){c=fgetc(stdin);if (c==‘q‘)i=1;elsei=0;}fprintf(stderr,"%d ",i);}printf("\n you hit %c. \n",c);nonblock(NB_DISABLE);return 0;} Press 'q' will lead the program to quit, else you will see the print of

described in detail here.resolves shared memory between processes, causing a deadlock problem due to a process exception exitNow that the problem has been confirmed is to get read lock after the process abnormal exit caused, I write a test program to reproduce the problem(! 2293)-gt; Cat Test/read_shared.cpp#includesharedupdatedata* _sharedupdatedata = NULL;cm_sub::cmmapfile* _mmapfile = NULL;int32_t initsharedmemread (const std::stringamp; Mmap_file_path){_mmapfile = new (Std::nothrow) cm_sub:

The Usleep () function delays code execution for several microseconds. The unpack () function unpack the data from a binary string. The Uniqid () function generates a unique ID based on the current time in microseconds. The Time_sleep_until () function delays code execution until the specified time. The Time_nanosleep () function delays code execution for several seconds and nanoseconds. The sleep () function delays code execution for several seconds.

judgment, let the client request if ($times >= 5) { echo "[]"; return; } If there is currently no readable data, wait 1 seconds to read again, if it takes a shorter time (this is quicker), use Usleep, the unit is millisecond sleep (1); Read ($id); } else { echo $result; Mysql_close ($link); } As code: //http://localhost/ajax/chat.php?type=rid=1 var lv:loadvars = new Loadvars (); Lv.load ("http://localho

)", "Realtime", "reduce");fprintf (stderr, "----------------------------------------------------\ n");for (i = 0; i {if (Delay[i] BreakNdelay = Delay[i];Test sleepGettimeofday (tvbegin, NULL);ret = Usleep (ndelay);if (ret = =-1){fprintf (stderr, "Usleep error, errno=%d [%s]\n", errno, Strerror (errno));}Gettimeofday (tvnow, NULL);Ntimetest = (tvnow.tv_sec-tvbegin.tv_sec) * 1000000 + tvnow.tv_usec-tvbegin.tv

(50,30) 7. Check whether the rectangle contains a point CGRect enemyrect = CGRectMake (0, 0, MB); Cgpoint hitPoint = Cgpointmake (m); if (Cgrectcontainspoint (Enemyrect, hitPoint)) { //yes! } 8. Check whether the two rectangles intersect CGRect playerrect = Ccrectmake (in); CGRect Minerect = CGRectMake (a); if (Cgrectintersectsrect (Playerrect, minerect)) { //ouch! } 9. CGRect and NSString conversion CGRect rect = CGRectMake (0, 0, MB); NSString *rects

= has_goaway ();If ($ status ){// Done}?> Execute the script scan_userstatus.php at regular intervals through crontab. # Echo "*: */10 ***/php_scripts/scan_userstatus.php" In this way, the script will be executed every 10 seconds. We found that in a short time, the memory resources of the script have not been released, and a new script has been enabled. That is to say, the new script is started, and the resources occupied by the old script have not been released as expected. This wastes a

expected. This wastes a lot of memory resources over time. We have improved the script as follows:@ File:/php_scripts/scan_userstatus.phpCopy codeThe Code is as follows:#/Usr/bin/env php-qWhile (1 ){$ Status = has_goaway ();If ($ status ){// Done}Usleep (10000000 );}?> In this way, no crontab is required. Run the following command to execute the script to achieve the same functional effect:# Chmod + x/php_scripts/scan_userstatus.php# Nohup/php_script

AbstractSince the CPU speed is too fast, many people cannot see the result at all. Therefore, how can we find C in the case of niosii if we want to stop running for n seconds and then try again? IntroductionEnvironment: US us II 7.2 SP3 + niosii eds 7.2 SP3 + de2 (Cyclone II ep2c35f627c6)This example uses(Formerly known) de2_nios_lite 1.1 (SOC) (nano II) (Systems builder) (μC/OS-II) (de2)For example The usleep () function is provided in unistd. H.

~Use in closures self Use[weak self]There is a detail, that isselfIn the closureOptionalFrom the code aboveself?.doSomething()We can see that. But if you use it in this closureself？(Multiple Useself？), The problem arises, becauseself？Is a weak reference, so you cannot determine allself？All operations can be completed. After all, if the referencedselfYou may get down at any time, and then raise an angry question: Figure 4 class C { deinit { println("Destroying C") } func log(msg: String)

(i = 0; i { if (Delay[i] Break ; Ndelay = Delay[i]; //test Sleep Gettimeofday (tvbegin, NULL); ret = Usleep (ndelay); if (ret = =-1) { fprintf (stderr, "Usleep error, errno=%d [%s]\n", errno, Strerror (errno)); } Gettimeofday (tvnow, NULL); Ntimetest = (tvnow.tv_sec-tvbegin.tv_sec) * 1000000 + tvnow.tv_usec-tvbegin.tv_usec; Nreduce = Ntimetest-ndelay; fprintf (stderr, "

#include #include#include#include"Ringbuffer.h"Static intB_flag =0;p thread_mutex_t Mutex=Pthread_mutex_initializer;#defineTx_lock (LOCK) pthread_mutex_lock (lock)#defineTx_unlock (Lock) Pthread_mutex_unlock (lock)void* Readbufferthread (void*param) {Ringbuffer* pstring = (Ringbuffer *) param; FILE* Fpout =NULL; size_t ret=0; Uint8 szbuf[ -*1024x768] = {0}; intNlen =0; Fpout= fopen ("File.bak","W"); if(Fpout = =NULL) { returnNULL; } while(B_flag) {tx_lock (mutex); Nlen= Ringbuffer_rea

time, wasted a lot of memory resources. We've made some improvements to this script, and the improvements are as follows: @file:/php_scripts/scan_userstatus.php Copy Code code as follows: #/usr/bin/env Php-q while (1) { $status = Has_goaway (); if ($status) { Done } Usleep (10000000); } ?> In this way, no need for crontab. The script can be executed with the following command to achieve the same functional effe