Function Realloc ()() in C

This guide covers function realloc ()() in c with practical context and easy-to-follow details. Use it to understand the subject and apply the information confidently.

Declare the Function Realloc ()() in C

Below is the declaration for realloc () in C:

 void * realloc ( void * ptr , kich - co ) 

Parameters

Ptr : This is the pointer to the previously allocated memory block with Malloc , Calloc Or realloc to be re-allocated. If the value is NULL, a new block is allocated and a pointer to it is returned by this function.

Kich-co : This is the new size for the memory block. If The value is 0 and the pointer ptr points to an existing Memory block, the memory block pointed to by ptr is freed and a NULL Pointer is returned.

Returns the Value

This function returns a pointer to the newly allocated memory, or returns NULL if the request fails.

For Example

The following C program illustrates the usage of realloc () in C:

 #include #include #include int main () { char * str ; /* lan cap phat bo nho ban bau */ str = ( char *) malloc ( 15 ); strcpy ( str , "QTM" ); printf ( "Chuoi = %s, tai Dia chi = %un" , str , str ); /* tai cap phat lai bo nho */ str = ( char *) realloc ( str , 25 ); strcat ( str , "@gmail.com" ); printf ( "Chuoi = %s, tai Dia chi = %un" , str , str ); free ( str ); return ( 0 ); } 

Compile and run the above C program to see the results.

According to Tutorialspoint

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