記憶體動態配置

1. 動態配置記憶體範例：宣告為 char 指標，使用前以 malloc 函式配置記憶體大小。

   [dywang@deyu zzz]$ vim malloc1.c 
   [dywang@deyu zzz]$ cat malloc1.c 
   #include <stdio.h>
   #include <stdlib.h>
   #include <string.h>
   
   int main() {
   	char name[20];
   	char *description;
   
   	strcpy(name, "De-Yu Wang");
   
   	description = malloc( 10 * sizeof(char) );
   	if( description == NULL ) {
   		fprintf(stderr, "Error - unable to allocate required memory\n");
   		return 1;
   	} else {
   		strcpy( description, "CSIE CYUT");
   	}
   	printf("Name: %s\n", name );
   	printf("Description: %s\n", description );
   	return 0;
   }
   

2. 編譯

   [dywang@deyu zzz]$ gcc -o malloc1 malloc1.c
   

3. 執行

   [dywang@deyu zzz]$ ./malloc1 
   Name: De-Yu Wang
   Description: CSIE CYUT