fdopen

FILE *fdopen (int fileHandle, const char mode[]);

Purpose

Obtains a pointer to a buffered I/O stream from a file handle returned by one of the following functions:

• open—Low-level I/O
• sopen—Low-level I/O (Windows only)

The returned value can be used as if it had been returned by fopen.

Parameters

Input
Name	Type	Description
fileHandle	int	A file handle returned by one of the following functions: OpenFile—Formatting and I/O library open—Low-level I/O sopen—Low-level I/O (Windows only)
mode	const char []	Specifies the mode of reading and writing desired for the opened file. The possible modes are listed in the following chart. Note  You should use a mode that is consistent with the mode in which you originally opened the file. If you use write capabilities not enabled when the file handle was originally opened, the call to fdopen succeeds, but any attempt to write fails. For instance, if you originally opened the file for reading only, you can pass "rw" to fdopen, but any call to fwrite fails. Mode argument Description r Open text file for reading. w Truncate to zero length or create text file for writing. a Append; open or create text file for writing at end-of-file. rb Open binary file for reading. wb Truncate to zero length or create binary file for writing. ab Append; open or create binary file for writing at end-of-file. r+ Open text file for reading and writing. w+ Truncate to zero length or create text file for reading and writing. a+ Append; open or create text file for reading and appending. rb+ Open binary file for reading and writing. wb+ Truncate to zero length or create binary file for reading and writing. ab+ Append; open or create binary file for reading and appending.

Return Value

Additional Information

Library: ANSI C Library

Include file: ansi_c.h

LabWindows/CVI compatibility: LabWindows/CVI 4.0 and later