Method

GioPollableInputStreamread_nonblocking

Declaration

gssize
g_pollable_input_stream_read_nonblocking (
  GPollableInputStream* stream,
  void* buffer,
  gsize count,
  GCancellable* cancellable,
  GError** error
)

Description

Attempts to read up to count bytes from stream into buffer, as with g_input_stream_read(). If stream is not currently readable, this will immediately return G_IO_ERROR_WOULD_BLOCK, and you can use g_pollable_input_stream_create_source() to create a GSource that will be triggered when stream is readable.

Note that since this method never blocks, you cannot actually use cancellable to cancel it. However, it will return an error if cancellable has already been cancelled when you call, which may happen if you call this method after a source triggers due to having been cancelled.

Parameters

buffer

Type: An array of guint8

A buffer to read data into (which should be at least count bytes long).

The argument will be set by the function.
The length of the array is specified in the count argument.
The data is owned by the caller of the function.
count

Type: gsize

The number of bytes you want to read.

cancellable

Type: GCancellable

A GCancellable, or NULL.

The argument can be NULL.
The data is owned by the caller of the function.
error

Type: GError **

The return location for a recoverable error.

The argument can be NULL.
If the return location is not NULL, then you must initialize it to a NULL GError*.
The argument will left initialized to NULL by the method if there are no errors.
In case of error, the argument will be set to a newly allocated GError; the caller will take ownership of the data, and be responsible for freeing it.

Return value

Type: gssize

The number of bytes read, or -1 on error (including G_IO_ERROR_WOULD_BLOCK).