以下是一些显示问题的示例代码 – 任何线索？

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <unistd.h>

int main(int argc,char *argv[]) {
    char * filename = argv[1];
    int fd;
    off_t size = 1UL << 40; // 30 == 1GB,40 == 1TB

    fd = open(filename,O_RDWR | O_CREAT | O_TRUNC,0666);
    ftruncate(fd,size);
    printf("Created %ld byte sparse file\n",size);

    char * buffer = (char *)mmap(NULL,(size_t)size,PROT_READ | PROT_WRITE,MAP_SHARED,fd,0);
    if ( buffer == MAP_Failed ) {
        perror("mmap");
        exit(1);
    }
    printf("Done mmap - returned 0x0%lx\n",(unsigned long)buffer);

    strcpy( buffer,"cafebabe" );
    printf("Wrote to start\n");

    strcpy( buffer + (size - 9),"deadbeef" );
    printf("Wrote to end\n");

    if ( munmap(buffer,(size_t)size) < 0 ) {
        perror("munmap");
        exit(1);
    }
    close(fd);

    return 0;
}

解决方法

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