#include <stdio.h> #include <malloc.h> #include <stdlib.h> int main( void ) { long *buffer, *oldbuffer; size_t size; if( (buffer = (long *)malloc( 1000 * sizeof( long ) )) == NULL ) exit( 1 ); size = _msize( buffer ); printf( "Size of block after malloc of 1000 longs: %u/n", size ); // Reallocate and show new size: oldbuffer = buffer; // save pointer in case realloc fails if( (buffer = realloc( buffer, size + (1000 * sizeof( long )) )) == NULL ) { free( oldbuffer ); // free original block exit( 1 ); } size = _msize( buffer ); printf( "Size of block after realloc of 1000 more longs: %u/n",size ); free( buffer ); exit( 0 ); }
执行结果：
Size of block after malloc of 1000 longs: 4000 Size of block after realloc of 1000 more longs: 8000 Press any key to continue
