c++ - 将 Linux 打开、读取、写入、关闭功能转换为在 Windows 上工作

Question

下面的代码是为 Linux 编写的，使用了打开、读取、写入和关闭。我在 Windows 计算机上工作，我通常在其中使用 fopen、fgets、fputs、fclose。现在，我收到打开、读取、写入和关闭的无原型(prototype)错误。是否有我可以包含的头文件以使其在 Windows 计算机上运行，​​或者我是否需要转换代码？你能展示如何转换它以便它在 Windows 上工作相同，或者至少让我指向一个显示如何转换它的在线文档吗？

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#ifdef unix
#include <unistd.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#ifndef O_BINARY
#define O_BINARY 0
#endif

#define NB 8192
char buff[NB];

int
main(argc,argv)
int argc;
char **argv;
{
int fdi, fdo, i, n, m;
char *p, *q;
char c;


if( argc > 0 )
    printf( "%s:  Reverse bytes in 8-byte values \n", argv[0] );
if( argc > 1 )
    strcpy( buff, argv[1] );
else
    {
    printf( "Input file name ? " );
    gets( buff );
    }
fdi = open( buff, O_BINARY | O_RDONLY, S_IREAD );

if( fdi <= 0 )
    {
    printf( "Can't open <%s>\n", buff );
    exit(2);
    }

if( argc > 2 )
    strcpy( buff, argv[2] );
else
    {
    printf( "Output file name ? " );
    gets( buff );
    }
fdo = open( buff, O_BINARY | O_RDWR | O_CREAT | O_TRUNC,
      S_IREAD | S_IWRITE );
if( fdo <= 0 )
    {
    printf( "Can't open <%s>\n", buff );
    exit(2);
    }

while( (n = read( fdi, buff, NB )) > 0 )
    {
    m = n / 8;
    p = buff;
    q = buff+7;
    for( i=0; i<m; i++ )
        {
        c = *p;
        *p++ = *q;
        *q-- = c;
        c = *p;
        *p++ = *q;
        *q-- = c;
        c = *p;
        *p++ = *q;
        *q-- = c;
        c = *p;
        *p++ = *q;
        *q-- = c;
        p += 4;
        q += 12;
        }
    write( fdo, buff, n );
    }
close( fdo );
close( fdi );
exit(0);
}

Answer 1

Microsoft 直接支持 POSIX 风格的低级 IO 调用，例如 open() , read() , , write() , 和 close() ;尽管似乎带有误导性的“已弃用”特征。

所需的 header 是 <io.h> .

调用对应于以前面的下划线命名的函数，因此 open() 映射到 _open() .

The full list of supported "low-level" IO functions Microsoft supports are :

低级 I/O

Low-Level I/O Functions

Function                                Use
_close                                  Close file
_commit                                 Flush file to disk
_creat, _wcreat                         Create file
_dup                                    Return next available file descriptor for given file
_dup2                                   Create second descriptor for given file
_eof                                    Test for end of file
_lseek, _lseeki64                       Reposition file pointer to given location
_open, _wopen                           Open file
_read                                   Read data from file
_sopen, _wsopen, _sopen_s, _wsopen_s    Open file for file sharing
_tell, _telli64                         Get current file-pointer position
_umask, _umask_s                        Set file-permission mask
_write                                  Write data to file

一些低级函数可能没有非下划线、POSIX 风格的等效名称。