記憶體重新配置

1. 重新配置記憶體函式 realloc() 及釋放記憶體函式 free() 範例：

   [dywang@deyu zzz]$ vim malloc2.c
   [dywang@deyu zzz]$ cat malloc2.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");
   	}
   	description = malloc( 100 * sizeof(char) );
   	if( description == NULL ) {
   		fprintf(stderr, "Error - unable to allocate required memory\n");
   		return 1;
   	} else {
   		strcpy( description, "ChaoYang University of Technology");
   	}
   	printf("Name = %s\n", name );
   	printf("Description: %s\n", description );
   	free(description);
   
   	return 0;
   }
   

2. 編譯

   [dywang@deyu zzz]$ gcc -o malloc2 malloc2.c
   

3. 執行

   [dywang@deyu zzz]$ ./malloc2
   Name = De-Yu Wang
   Description: ChaoYang University of Technology