我知道这与Windows和Linux中的行尾指示符之间的差异有关，但我不知道如何修复它。
我确实看过帖子 Getting std :: ifstream to handle LF, CR, and CRLF? 但是当我使用该帖子的简化版本时（我使用直接读取而不是缓冲读取，知道存在性能损失，但现在想要保持简单），它没有解决我的问题所以我希望在这里提供一些指导。我测试了我的帖子的修改版本，它确实成功找到并替换了我临时用于测试场景的字符和标签，所以逻辑工作但我仍然有问题。
我知道我在这里遗漏了一些非常基本的东西，当有人帮助我解决这个问题时，我可能会觉得非常愚蠢，所以我宁愿不公开承认我的愚蠢但我已经在这方面工作了一个星期了无法解决，所以我正在寻求帮助。
我是C ++的新手，所以如果我在这里做一些非常棒的话，请温柔地回答你： - ）
我有以下单文件程序，我已经创建了原型，我想做什么。所以这是一个简单的例子，但我需要让它继续下去。这不是作业问题;我真的需要解决这个问题来创建一个应用程序。
该计划（如下所示）：
编译时没有错误或警告，并在CentOS盒子上干净利落地运行;
在CentOS盒子上使用mingw32交叉编译时没有错误或警告，并且在Windows上运行干净;
所以是的，它与linux和Windows之间的不同文件格式有关，它可能与换行代码有关，但我试图适应它并且它不起作用。
为了使它更复杂，我发现旧的Mac换行符再次不同：
请帮忙！ ...
我想：
所以我需要检查文件，确定正在使用的换行符并相应地处理
有什么建议吗？
我当前（简化的）代码（尚未进行验证检查）是：
[代码]
int main(int argc, char** argv)
{
std::string rc_input_file_name = "rc_input_file.txt";
std::string rc_output_file_name = "rc_output_file.txt";
char * RC_INPUT_FILE_NAME = new char[ rc_input_file_name.length() + 1 ];
strcpy( RC_INPUT_FILE_NAME, rc_input_file_name.c_str() );
char * RC_OUTPUT_FILE_NAME = new char[ rc_output_file_name.length() + 1 ];
strcpy( RC_OUTPUT_FILE_NAME, rc_output_file_name.c_str() );
bool failure_flag = false;
std::ifstream rc_input_file_holder;
rc_input_file_holder.open( RC_INPUT_FILE_NAME , std::ios::in );
if ( ! rc_input_file_holder.is_open() )
{
std::cout << "Error - Could not open the input file" << std::endl;
failure_flag = true;
}
else
{
std::ofstream rc_output_file_holder;
rc_output_file_holder.open( RC_OUTPUT_FILE_NAME , std::ios::out | std::ios::trunc );
if ( ! rc_output_file_holder.is_open() )
{
std::cout << "Error - Could not open or create the output file" << std::endl;
failure_flag = true;
}
else
{
std::streampos char_num = 0;
long int line_num = 0;
long int starting_char_pos = 0;
std::string file_line = "";
while ( getline( rc_input_file_holder , file_line ) )
{
line_num = line_num + 1;
long int file_line_length = file_line.length() +1 ;
long int char_num = 0;
for ( char_num = 0 ; char_num < file_line_length ; char_num++ )
{
if ( file_line[ char_num ] == '\n' )
{
if ( char_num == file_line_length - 1 )
{
file_line[ char_num ] = '-';
}
else
{
if ( file_line[ char_num + 1 ] == '\n' )
{
file_line[ char_num ] = ' ';
}
else
{
file_line[ char_num ] = ' ';
}
}
}
}
int field_display_width = 4;
std::cout << "Line " << std::setw( field_display_width ) << line_num <<
", starting at character position " << std::setw( field_display_width ) << starting_char_pos <<
", contains " << file_line << "." << std::endl;
starting_char_pos = rc_input_file_holder.tellg();
rc_output_file_holder << "Line " << line_num << ": " << file_line << std::endl;
}
rc_input_file_holder.close();
rc_output_file_holder.close();
delete [] RC_INPUT_FILE_NAME;
delete [] RC_OUTPUT_FILE_NAME;
}
}
if ( failure_flag )
{
return EXIT_FAILURE;
}
else
{
return EXIT_SUCCESS;
}
}
[/代码]
相同的代码，有很多评论（为了我的学习经验）：
[代码]
/*
* The main function, from which all else is accessed
*/
int main(int argc, char** argv)
{
/*
*Program to:
* 1) read from a text file
* 2) do some validation checks on the content of that text file
* 3) output a report to another text file
*/
// Set the filenames to be used in this file-handling program
std::string rc_input_file_name = "rc_input_file.txt";
std::string rc_output_file_name = "rc_output_file.txt";
// Note that when the filenames are used in the .open statements below
// they have to be in a cstring format, not a string format
// so the conversion is done here once
// Use the Capitalized form of the file name to indicate the converted value
// (remember, variable names are case-sensitive in C/C++ so NAME is different than name)
// This conversion could be done 3 ways:
// - done each time the cstring is needed:
// file_holder_name.open( string_file_name.c_str() )
// - done once and referred to each time
// simple method:
// const char * converted_file_name = string_file_name.c_str()
// explicit method (2-step):
// char * converted_file_name = new char[ string_file_name.length() + 1 ];
// strcpy( converted_file_name, string_file_name.c_str() );
// This program uses the explicit method to do it once for each filename
// because by doing so, the char array created has variable length
// and you do not risk buffer overflow
char * RC_INPUT_FILE_NAME = new char[ rc_input_file_name.length() + 1 ];
strcpy( RC_INPUT_FILE_NAME, rc_input_file_name.c_str() );
char * RC_OUTPUT_FILE_NAME = new char[ rc_output_file_name.length() + 1 ];
strcpy( RC_OUTPUT_FILE_NAME, rc_output_file_name.c_str() );
// This will be set to true if either the input or output file cannot be opened
bool failure_flag = false;
// Open the input file
std::ifstream rc_input_file_holder;
rc_input_file_holder.open( RC_INPUT_FILE_NAME , std::ios::in );
// Validate that the input file was properly opened/created
// If not, set failure flag
if ( ! rc_input_file_holder.is_open() )
{
// Could not open the input file; set failure flag to true
std::cout << "Error - Could not open the input file" << std::endl;
failure_flag = true;
}
else
{
// Open the output file
// Create one if none previously existed
// Erase the contents if it already existed
std::ofstream rc_output_file_holder;
rc_output_file_holder.open( RC_OUTPUT_FILE_NAME , std::ios::out | std::ios::trunc );
// Validate that the output file was properly opened/created
// If not, set failure flag
if ( ! rc_output_file_holder.is_open() )
{
// Could not open the output file; set failure flag to true
std::cout << "Error - Could not open or create the output file" << std::endl;
failure_flag = true;
}
else
{
// Get the current position where the character pointer is at
// Get it before the getline is executed so it gives you where the current line starts
std::streampos char_num = 0;
// Initialize the line_number and starting character position to 0
long int line_num = 0;
long int starting_char_pos = 0;
std::string file_line = "";
while ( getline( rc_input_file_holder , file_line ) )
{
// Set the line number counter to the current line (first line is Line 1, not 0)
line_num = line_num + 1;
// Check if the new line designator uses the standard for:
// - linux (\n)
// - Windows (\r\n)
// - Old Mac (\r)
// Convert any non-linux new line designator to linux new line designator (\n)
long int file_line_length = file_line.length() +1 ;
long int char_num = 0;
for ( char_num = 0 ; char_num < file_line_length ; char_num++ )
{
// If a \r character is found, decide what to do with it
if ( file_line[ char_num ] == '\n' )
{
// If the \r char is the last line character (before the null terminator)
// the file use the old Mac format to indicate new line
// so replace the \r with \n
if ( char_num == file_line_length - 1 )
{
file_line[ char_num ] = '-';
}
else
// If the \r char is NOT the last line character (before the null terminator)
{
// If the next character is a \n, the file uses the Windows format to indicate new line
// so replace the \r with space
if ( file_line[ char_num + 1 ] == '\n' )
{
file_line[ char_num ] = ' ';
}
// If the next char is NOT a \n (and the pointer is NOT at the last line character)
// then for some reason, there is a \r in the interior of the string
// At this point, I do not know why this would be
// but I don't want it left there, so replace it with a space
// Yes, I know this is the same as the above action,
// but I left is separate to allow for future flexibility
else
{
file_line[ char_num ] = '-';
}
}
}
}
// Output the contents of the line just fetched
// This is done in this prototype file as a placeholder
// In the real program, this is where the validation check(s) for the line would occur)
// and would likely be done in a function or class
// The setw() function requires #include <iomanip>
int field_display_width = 4;
std::cout << "Line " << std::setw( field_display_width ) << line_num <<
", starting at character position " << std::setw( field_display_width ) << starting_char_pos <<
", contains " << file_line << "." << std::endl;
// Reset the character pointer to the end of this line => start of next line
starting_char_pos = rc_input_file_holder.tellg();
// Output the (edited) contents of the line just fetched
// This is done in this prototype file as a placeholder
// In the real program, this is where the results of the validation checks would be recorded
// You could put this in an if statement and record nothing if the line was valid
rc_output_file_holder << "Line " << line_num << ": " << file_line << std::endl;
}
// Clean up by:
// - closing the files that were opened (input and output)
// - deleting the character arrays created
rc_input_file_holder.close();
rc_output_file_holder.close();
delete [] RC_INPUT_FILE_NAME;
delete [] RC_OUTPUT_FILE_NAME;
}
}
// Check to see if all operations have successfully completed
// If so exit this program with success indicated
// If not,exit this program with failure indicated
if ( failure_flag )
{
return EXIT_FAILURE;
}
else
{
return EXIT_SUCCESS;
}
}
[/代码]
我拥有所有正确的包含，并且在为Linux编译或为Windows交叉编译时没有生成错误或警告。
我使用的输入文件只有5行（愚蠢）文本：
A new beginning
just in case
the file was corrupted
and the darn program was working fine ...
at least it was on linux
并且linux上的输出正如预期的那样：
Line 1, starting at character position 0, contains A new beginning.
Line 2, starting at character position 16, contains just in case.
Line 3, starting at character position 29, contains the file was corrupted.
Line 4, starting at character position 52, contains and the darn program was working fine ....
Line 5, starting at character position 94, contains at least it was on linux.
当我在linux中导入文本文件创建时，Windows中的输出是相同的，但是当我使用记事本并在Windows中手动重新创建相同的文件时，输出是
Line 1, starting at character position 0, contains A new beginning.
Line 2, starting at character position 20, contains t in case.
Line 3, starting at character position 33, contains e file was corrupted.
Line 4, starting at character position 56, contains nd the darn program was working fine ....
Line 5, starting at character position 98, contains at least it was on linux.
注意2,3,4和5行的起始字符位置的差异 请注意第2,3和4行开头的缺失字符
欢迎任何和所有想法...
答案 0 :(得分：0)
见
处的决议为了解决这个问题，通过apt-get install安装的mingw交叉编译器已经过时了。当我手动安装更新的交叉编译器并更新设置以防止出现一些错误消息时，一切正常。