Few Queries Please do answer

[bindiya182003]

Few Queries:

1. Difference between parameters and arguments while calling a function?
2. Difference between memcpy() and memset()?
3. Difference between memcmp() and strcmp()?
4. What happens in this code:
main()
{
char arr[3];
arr[0]=0;
arr[1]='0';
printf("%s,%s,%s",&arr[0],&arr[1],&arr[3],&arr[2]);
}

Please help me

[Meetee]

Hi,

These topics are easily available and explained in various sites. You can search on google by pasting the same lines there. Also run the program and see the output :)

Regards

[bindiya182003]

Hi,

These topics are easily available and explained in various sites. You can search on google by pasting the same lines there. Also run the program and see the output :)

Regards

I know that from google I will get answers for these question. Since I didn't get a satisfying answers I asked in this site.And I got every good answer from this site people.Thanks a lot for your help.Other questions answers also I will get from google then whats the use of this site.Then regarding the output i wanted an explanation. Really sad to get such a reply.And sorry for disturbing you people.

[Meetee]

I know that from google I will get answers for these question. Since I didn't get a satisfying answers I asked in this site.And I got every good answer from this site people.Thanks a lot for your help.Other questions answers also I will get from google then whats the use of this site.Then regarding the output i wanted an explanation. Really sad to get such a reply.And sorry for disturbing you people.

That is why you should read posting guidelines. Whatever you wrote in your second post, you should write it in your first post. Then reader can understand that you have taken efforts, as we are not allowed to spoonfeed and self work is the best help. That's why I wrote such answer to work by yourself as I was not known that you have worked so far.

Anyways,
Your first answer is :

When a function is defined, the expected variables are listed in parentheses. These are parameters.

For example:

void fun(length)
{
.....
}

here length is a parameter of the Square function.

When a function is called, there is a list of variables that are passed to the function. These are arguments. Like:

int length = fun(length);
 

For memset and memcpy you can refer http://www.cplusplus.com/reference/c...ng/memset.html (Thanks to Google search)

Difference between memcmp and strcmp is:strcmp() compares characters up until it sees the first '\0' in either string. As soon as character difference is found or '\0' is found it returns while memcmp() does not look for '\0'. It looks for the first difference considering the size specified.

For that output experts may help!!

Regards

[bindiya182003]

That is why you should read posting guidelines. Whatever you wrote in your second post, you should write it in your first post. Then reader can understand that you have taken efforts, as we are not allowed to spoonfeed and self work is the best help. That's why I wrote such answer to work by yourself as I was not known that you have worked so far.

Anyways,
Your first answer is :

When a function is defined, the expected variables are listed in parentheses. These are parameters.

For example:

void fun(length)
{
.....
}

here length is a parameter of the Square function.

When a function is called, there is a list of variables that are passed to the function. These are arguments. Like:

int length = fun(length);
 

For memset and memcpy you can refer http://www.cplusplus.com/reference/c...ng/memset.html (Thanks to Google search)

Difference between memcmp and strcmp is:strcmp() compares characters up until it sees the first '\0' in either string. As soon as character difference is found or '\0' is found it returns while memcmp() does not look for '\0'. It looks for the first difference considering the size specified.

For that output experts may help!!

Regards

Thanks a lot for your reply...Because I was in a hurry i was not able to post the details....And I was really in need of these things in my office work...

Anywayz thanks for your help..Sorry for getting rude.

[Banfa]

4. What happens in this code:

    main()
    {
     char arr[3];
     arr[0]=0;
     arr[1]='0';
     printf("%s,%s,%s",&arr[0],&arr[1],&arr[3],&arr[2]);
     }
 

This program invokes undefined behaviour on at least 2 counts and probably 4. The output could therefore be anything. Undefined behaviour is bad, as soon as it is invoked the compiler/program is free to do anything it chooses.

Here is a list of the problems causing undefined behaviour

• main MUST return int.
• &arr[3] is an out of bounds array access.
• &arr[1] and &arr[2]. At compile time these are not specifically undefined behaviour. However you have told printf they are pointers to strings, it will keep printing the characters until it finds a '\0' character. Unless arr[2] == '/0' this means it will access memory outside the bounds of the array. Since arr is on the stack it is not initialised and arr[2] is never set so it will be unlikely to have the value '\0'. This means that both these expressions will probably cause an out of bounds array access which, as above invokes undefined behaviour.

[weaknessforcats]

1. Difference between parameters and arguments while calling a function?

A parameter is the value of the argument.

For functions you have arguments. When you call the function you provide the parameter.

The same applies to templates. Templates have arguments for the type. When you supply the types at compile time, you parameterize the template. That's why templates are called parameterized types.