If additional characters follow the sequence, the behavior depends on the library implementation: some implementations may ignore additional characters so that for example an additional "t" sometimes used to explicitly state a text file is accepted.
Repositioning operations fseekfsetposrewind affects the next input operations, but output operations move the position back to the end of file.
The application must explicitly specify the name of the C runtime functions, both existing version and bit version, to use. Output operations always write data at the end of the file, expanding it.
The operations that are allowed on the stream and how these are performed are defined by the mode parameter. Return Value If the file is successfully opened, the function returns a pointer to a FILE object that can be used to identify the stream on future operations.
LIB file system. If the given file exists, its contents are cleared unless it is a logical file. The existing C runtime functions and the relevant data types in the code will all be automatically mapped or redefined to their bit versions.
For files in the integrated file system that are larger than 2 GB, you need to allow your application programs access to bit C runtime functions.