函数名: malloc 
 功  能: 内存分配函数 
 用  法: #include <alloc.h> 
         void *malloc(unsigned size); 
 程序例: 
#include <stdio.h> 
 #include <string.h> 
 #include <alloc.h> 
 #include <process.h> 
int main(void) 
 { 
    char *str; 
   /* allocate memory for string */ 
    /* This will generate an error when compiling */ 
    /* with C++, use the new operator instead. */ 
    if ((str = malloc(10)) == NULL) 
    { 
       printf("Not enough memory to allocate buffer\n"); 
       exit(1);  /* terminate program if out of memory */ 
    } 
   /* copy "Hello" into string */ 
    strcpy(str, "Hello"); 
   /* display string */ 
    printf("String is %s\n", str); 
   /* free memory */ 
    free(str); 
   return 0; 
 }