Libssh2 channel read ex

From Libssh2

int libssh2_channel_read_ex(LIBSSH2_CHANNEL *channel, int stream_id,
                            char *buf, size_t buflen);
#define libssh2_channel_read(channel, buf, buflen) \
        libssh2_channel_read_ex((channel), 0, (buf), (buflen))
#define libssh2_channel_read_stderr(channel, buf, buflen) \
        libssh2_channel_read_ex((channel), SSH_EXTENDED_DATA_STDERR, (buf), (buflen))

About

Attempt to read data from an active channel stream. All channel streams have one standard I/O substream (stream_id == 0), and may have up to 2^32 extended data streams as identified by the selected stream_id. The SSH2 protocol currently defines a stream ID of 1 to be the stderr substream.

Parameters

• channel

  Active channel stream to read from.

• stream_id

  Substream ID number (e.g. 0 or SSH_EXTENDED_DATA_STDERR)

• buf

  Allocated storage buffer to read data into.

• buflen

  Maximum size of buf storage.

Returns

• Actual number of bytes read