mmap()函数和munmap()函数的例子

代码：

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>#define FILELENGTH 80
int main(void)
{int fd=-1;char buf[]="quick brown fox jumps over the lazy dog";char *ptr=NULL;fd=open("mmap.txt",O_RDWR|O_CREAT|O_TRUNC,S_IRWXU);if(-1==fd){return -1;}lseek(fd,FILELENGTH-1,SEEK_SET);write(fd,buf,1);ptr=(char*)mmap(NULL,FILELENGTH,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0);if((char*)-1==ptr){printf("mnap failure\n");close(fd);return -1;}memcpy(ptr+16,buf,strlen(buf));munmap(ptr,FILELENGTH);close(fd);return 0;
}

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