memset

[swat]

why use memset and what does memset(a,0,sizeof(a)); represents?can some one make me clear abt memset with some examples?thanks..

[Manjiri]

why use memset and what does memset(a,0,sizeof(a)); represents?can some one make me clear abt memset with some examples?thanks..

If you are going to declare say a array dianamically.... after allocating memory by using malloc or calloc... U can use the memset function to intialise the elements of array with null....


(a,0,sizeof(a));

It syas that a is array and you are going to initailse the elements with null....

For example

#include<stdio.h>
int  main()
{
char *s;
s=(char*) malloc(20);
memset(s,'\0',20);
printf("Enter your name\n");
gets(s);
printf("your name is\n");
puts(s);
return 0;
}  

Hope you are satisfied with ans...

[r035198x]

"The Standard C library function memset( ) (in <cstring>) is used for convenience .... It sets all memory starting at a particular address (the first argument) to a particular value (the second argument) for n bytes past the starting address (n is the third argument). Of course, you could have simply used a loop to iterate through all the memory, but memset( ) is available, well-tested (so it’s less likely you’ll introduce an error), and probably more efficient than if you coded it by hand."


From Thinking in c++

[rsr]

thanks for all the replies