Difference Between Files Written in Binary and Text Mode

Difference between files written in binary and text mode

I believe that most platforms will ignore the "t" option or the "text-mode" option when dealing with streams. On windows, however, this is not the case. If you take a look at the description of the fopen() function at: MSDN, you will see that specifying the "t" option will have the following effect:

• line feeds ('\n') will be translated to '\r\n" sequences on output
• carriage return/line feed sequences will be translated to line feeds on input.
• If the file is opened in append mode, the end of the file will be examined for a ctrl-z character (character 26) and that character removed, if possible. It will also interpret the presence of that character as being the end of file. This is an unfortunate holdover from the days of CPM (something about the sins of the parents being visited upon their children up to the 3rd or 4th generation). Contrary to previously stated opinion, the ctrl-z character will not be appended.

Differences between writing/reading binary/text in c

Just do everything with "binary" files. Linux has no difference between "text" and "binary" in a file on OS level, there are just files with bytes in it. Ie. expect that a file contains every possible byte value, and don´t write different code for different kinds of content.

There is a difference in Windows: Text mode in Windows means that a line break (\n) in the program gets converted to/from \r\n when writing to / reading from a file. The written text file read in binary mode will contain this two bytes instead of the original \n and vice-versa. (Additionally, MS isn´t very clear in the documentation that this is the only difference, it can confuse beginners easily.)

If you use standard C fopen and fclose instead of Linux-specific open etc., you can specify to open a file in binary or text mode (on Linux too). This is because code with fopen should work on Windows and Linux without any OS-specific changes; but what you choose in fopen doesn´t matter when running on Linux (which can be verified by reading the source code of fopen etc.)

And about the sockets:

Linux: No difference (again)

Windows: No difference too. There are just bytes, and no strange line break conversions.

Difference between text mode and binary mode in c

In a sense, binary mode is "raw": nothing is translated, since it has no basis for doing so. Whereas in text mode, the file is interpreted as text, and thus (for example) line endings get translated to the appropriate representation.

Difference between opening a file in binary vs text

The link you gave does actually describe the differences, but it's buried at the bottom of the page:

http://www.cplusplus.com/reference/cstdio/fopen/

Text files are files containing sequences of lines of text. Depending on the environment where the application runs, some special character conversion may occur in input/output operations in text mode to adapt them to a system-specific text file format. Although on some environments no conversions occur and both text files and binary files are treated the same way, using the appropriate mode improves portability.

The conversion could be to normalize \r\n to \n (or vice-versa), or maybe ignoring characters beyond 0x7F (a-la 'text mode' in FTP). Personally I'd open everything in binary-mode and use a good Unicode or other text-encoding library for dealing with text.

C++ Is using files in Binary mode better or worse then text mode?

The only difference between binary and text access is who does the interpretation of a sequence of bytes in a stream.

• When you use binary mode, the task of interpreting the sequence of bytes is entirely yours: your program gets access to "raw" bytes, and that is that.
• When you use text mode, the standard library takes on the task of interpreting bytes as a sequence of characters for you. The standard does not guarantee cross-system portability of this interpretation, but it will be correct for the system for which your program is compiled.

Another thing to note is that all text files can be processed in binary mode, while opening binary files in text mode may be problematic.

In general, if you need a portable text encoding, you should access files in binary mode and do interpretation yourself, or use a custom library that would do it for you.

Difference between binary and text I/O in python on Windows

This mode is about conversion of line endings.

When reading in text mode, the platform's native line endings (\r\n on Windows) are converted to Python's Unix-style \n line endings. When writing in text mode, the reverse happens.

In binary mode, no such conversion is done.

Other platforms usually do fine without the conversion, because they store line endings natively as \n. (An exception is Mac OS, which used to use \r in the old days.) Code relying on this, however, is not portable.

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