What is delay() in C? Is it a system function?

Question

In a book, I saw a piece of code.

but when I ran this code it said: C:\Users\dipankar\Desktop\cla.cpp [Error] 'delay' was not declared in this scope

They used it without proper documentation. They only said that "delay() is used to delay the execution of the next line by few milliseconds"!!. please help.

You should always post the code and not a screenshot of the code. — Lasoloz, Apr 30 '17 at 18:31
There is a pretty straightforward help in the editor about this: indent by four spaces, and the line will be highlighted automatically. — Lasoloz, Apr 30 '17 at 18:38

score 7 · Accepted Answer · answered Apr 30 '17 at 18:42

The book you are reading is crap. Avoid the book and tell others to do the same.

<conio.h> is a system-specific header and not guaranteed to be available on many platforms.
The result of fgetc must never be stored in a char variable.
The function feof must never be used in a loop condition.

The book probably comes from the 1980s or early 1990s. There is a function delay in Turbo Pascal that takes milliseconds. Maybe that's the one the author means.

score 3 · Answer 2 · answered Apr 30 '17 at 18:33

3

It's a millisecond delay function. Where it's defined depends a lot on what platform/toolchain you're compiling against. Often it would be found in <time.h>

answered Apr 30 '17 at 18:33

ctacke

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i have added #include but same result !! – dipankar pal Apr 30 '17 at 18:38
Again, it greatly depends on your platform and toolchain. We have no idea what you're targeting or what would be "standardly" available. We can't even really suggest a modern equivalent without that info. – ctacke Apr 30 '17 at 18:58

score 0 · Answer 3 · answered Apr 30 '17 at 18:35

0

I am not aware of any sleep function as part of the C standard. However, you would use nanosleep (https://linux.die.net/man/2/nanosleep) for this purpose in Linux.

answered Apr 30 '17 at 18:35

eega

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What is delay() in C? Is it a system function?

3 Answers3