error: identifier "sytem" is undefined

Question

I have just started to learn C language and I'm just trying to write Hello World to get started but I get this error message. I'm sure the answer is obvious but can someone please tell me what I need to do? This is my code:

#include <stdio.h>

int main()
{
printf("Hello World ");
system("Pause");
    return 0;
}

`system("pause");` makes me cry. http://stackoverflow.com/questions/1107705/systempause-why-is-it-wrong — Fred Larson, Jan 16 '13 at 15:14
@FredLarson: FYI [Markdown Link](http://daringfireball.net/projects/markdown/syntax#link) syntax is supported in comments, useful to avoid long URLs. — , Jan 16 '13 at 15:24

Raghu Srikanth Reddy · Answer 1 · 2013-01-16T15:20:10.447

3

#include<stdlib.h>

Include this header file..

edited Jan 16 '13 at 15:20

answered Jan 16 '13 at 15:12

Raghu Srikanth Reddy

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Mike · Answer 2 · 2013-01-16T15:35:27.570

You need to add another header file:

#include <stdlib.h>

When you have an undefined call like this you can always throw "man 3 system" and you'll get something like this so you can see if you're missing a header file.

FYI, for your specific program, you may want to consider no using system("Pause") since it's system dependent. It would be better to pause with a break point (if you're using an IDE) or something more C standard like getchar()

score 1 · Answer 3 · answered Jan 16 '13 at 15:11

1

You need to #include <stdlib.h>

If you aren't sure which header a standard function is defined in, its man page will tell you.

answered Jan 16 '13 at 15:11

simonc

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A better reference is the C standard, www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf. Search for "the nn function" where nn is the name of the function you are looking for. "man" contains various Linux-related goo that is not necessarily standard compliant. – Lundin Jan 16 '13 at 15:42

score 1 · Answer 4 · answered Jan 16 '13 at 15:13

1

Insert

#include <stdlib.h> //in C

or

#include <cstdlib> //in C++

before your main() function.

Note that your IDE should refrain from closing your program. If it doesn't, change IDE.

answered Jan 16 '13 at 15:13

milleniumbug

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score 1 · Answer 5 · answered Sep 10 '14 at 19:14

1

You should include the following library.

 #include <stdlib.h>

It's simple as that. I hope you find this useful.

answered Sep 10 '14 at 19:14

miksiii

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score 0 · Answer 6 · answered Jan 16 '13 at 15:41

0

As the others said, you need to include an header; if you're running on Linux, you may install "manpages-dev" package, and then tape "man system" which will tell you what are the headers you need to use.

answered Jan 16 '13 at 15:41

bagage

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error: identifier "sytem" is undefined

6 Answers6