Content

• Steps
• Method 1 of 2: For-loop technique
• Method 2 of 2: The "sleep ()" technique
• Sample code
• Tips
• Warnings

Have you ever wanted to create a C program that waits for a certain amount of time? You can customize the way to give the time "fly by", for example: when showing a pop-up page (notification or hint) for the game. ... OK, here are some ways to create a "stand still" program, read on ...

Steps

1. 1 Let your processor run for a while without causing an observable event.
2. 2 Do not perform any other operations during this delay to create a simple time delay.

Method 1 of 2: For-loop technique

1. 1 Use a typical "for" loop followed by an empty statement to implement a delay.
2. 2 Write as follows, for example:
   • for (i = 1; i100; i ++);
   • The operator following the ";" forces the computer to loop 100 times without a noticeable event. It only creates a time delay.

Method 2 of 2: The "sleep ()" technique

1. 1 Use sleep (). The function is called sleep (int ms), declared in TIME.H>, which makes the program wait for a specified amount of time in milliseconds.
2. 2 Include the following line in your program before int main ():
   • #include TIME.H>
3. 3 Paste where necessary to make your program delay:
   • sleep (1000);
   • Change "1000" to the number of milliseconds you want to wait (for example, if you want to make a 2 second delay, replace it with "2000".
   • Tip: On some systems, the value may be specified in seconds instead of milliseconds. Therefore, sometimes 1000 is not 1 second, but actually 1000 seconds.

Sample code

A program that waits for a certain number of seconds:

#include stdio.h> #include dos.h> int main () {int del; // The delay period printf ("Enter the delay time (in seconds):"); scanf ("% i",? del); del * = 1000; // Multiply it by 1000 to convert to milliseconds Delay (del); // Delay. printf ("Done."); return 0; }

A program that counts down from 10 to 0:

#include STDIO.H> #include TIME.H> int main () {int i; for (i = 10; i> = 0; i--) {printf ("% i n", i); // Write the current 'countdown' number Delay (1000); // Wait a second} return 0; }

Tips

• A millisecond is 1/1000 of a second.
• The above algorithm can be implemented using any looping structure followed by the null operator - "; as using while or do-while loops.

Warnings

• This method is generally useless for anything other than a trivial program. In general, use timers or an event-driven approach to accomplish this. Otherwise, the program will become unresponsive during the delay time and this is not always a good thing. Also, choosing N in a loop, if it depends on the execution of commands, can have unexpected results. Apparently the original author has never heard of an optimizing compiler ... it can optimize an entire loop if it doesn't actually do anything!
• Note that when using the "for-loop" method, it may take a very large interval for i, since the empty statement is very fast. Such large numbers may not fit into an integer type.
• If you use a for-loop, the compiler can optimize the code, and since the loop does nothing, remove it. This does not happen when using Delay ().