adder_example.c

linux下的程序开发：本程序主要实现内存的分配和管理

#include<stdio.h>
#include<string.h>
#include<sys/types.h>
#include<stdlib.h>
#include<unistd.h>
#define SHW_ADR(ID,I) printf("the id %s \t is at adr:%8X\n",ID,&I);

extern etext,edata,end;

char *cptr="Hello World\n";
char buffer1[25];
int main(void)
{
	void showit(char *);
	int i=0;
   	printf("Adr etext:%8x\tAdr edata:%8x \t Adr end :%8x \n\n",&etext,&edata,&end);
	SHW_ADR("main",main);
	SHW_ADR("showit",showit);
	SHW_ADR("cptr",cptr);
	SHW_ADR("buffer1",buffer1);
	SHW_ADR("i",i);
	strcpy(buffer1,"A demonstration\n");
	write(1,buffer1,strlen(buffer1)+1);
	for(;i<1;++i)
		showit(cptr);
	return 0;
}

void showit(char *p)
{
	char *buffer2;
	SHW_ADR("buffer2",buffer2);
	if((buffer2=(char *)malloc((unsigned)(strlen(p)+1)))!=NULL)
	{
		strcpy(buffer2,p);
		printf("%s",buffer2);
		free(buffer2);
	}
	else
	{
		printf("Allocation error.\n");
		exit(1);
	}
}