setvbuf() -- alter buffering behavior of stream

SYNOPSIS

#include <stdio.h>

int setvbuf(FILE *stream, char *buffer, int mode, size_t size);

The setvbuf() function lets the program control the buffer of a given stream. This function may be used after the stream pointed to by stream is associated with an open file, but before any other operation is performed on the stream. If buffer is not a NULL pointer, the array it points to is used instead of a buffer allocated by setvbuf().

PARAMETERS

stream

Points to a FILE structure.

buffer

Is the user-allocated buffer.

mode

Is the mode of buffering which may be one of the following:

_IOFBF: Causes input/output to be fully buffered.
_IOLBF: Causes input/output to be line buffered.
_IONBF: Causes input/output to be unbuffered.

size

Is the size of the buffer.

RETURN VALUES

If successful, setvbuf() returns 0. On failure, it returns non-zero if an invalid value is given for mode or if the request cannot be honored.

CONFORMANCE

ANSI/ISO 9899-1990.

MULTITHREAD SAFETY LEVEL

MT-Safe.

PORTING ISSUES

None.

AVAILABILITY

PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition

setvbuf()
alter buffering behavior of stream

Function