test for rgw file

test.cpp

#include <errno.h>
#include <iostream>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>

int32_t main(int32_t argc, char* argv[]) {
    if (argc != 2) {
        std::cout << "Usage: " << argv[0] << " file " << std::endl;
        return -1;
    }

    int32_t fd = open(argv[1], O_CREAT | O_TRUNC | O_WRONLY, 0600);
    if (fd == -1) {
        std::cerr << "failed to open: errno " << errno << " error " << strerror(errno) << std::endl;
        return -1;
    }

    std::cout << "open fd " << fd << std::endl;

    struct stat stat = {0};
    int32_t status = fstat(fd, &stat);
    std::cout << "fstat fd " << fd << " status " << status << std::endl;

    char* buffer = new char[916688];
    memset(buffer, 0, 916688);

    ssize_t bytes = write(fd, buffer, 916688);
    std::cout << "write fd " << fd << " bytes " << bytes << std::endl;
    if (bytes != 916688) {
        std::cerr << "failed to write: errno " << errno << " error " << strerror(errno) << std::endl;
        return -1;
    }
    delete [] buffer;

    buffer = new char[458276];
    memset(buffer, 0, 458276);

    bytes = write(fd, buffer, 458276);
    std::cout << "write fd " << fd << " bytes " << bytes << std::endl;
    if (bytes != 458276) {
        std::cerr << "failed to write: errno " << errno << " error " << strerror(errno) << std::endl;
        return -1;
    }
    delete [] buffer;

    int32_t ret = close(fd);
    std::cout << "close fd " << fd << " ret " << ret << std::endl;

    return 0;
}

the output is :

[root@192 ~]# ./test /mnt/abc12345
open fd 3
fstat fd 3 status 0
write fd 3 bytes 916688
write fd 3 bytes -1
failed to write: errno 5 error Input/output error