libssh2_channel_read_ex - read data from a channel stream

       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.

       channel - active channel stream to read from.

       stream_id - substream ID number (e.g. 0 or SSH_EXTENDED_DATA_STDERR)

       buf - pointer to storage buffer to read data into

       buflen - size of the buf storage

       libssh2_channel_read(3) and libssh2_channel_read_stderr(3) are macros.

LIBSSH2_ERROR_SOCKET_SEND - Unable to send data on socket.

       LIBSSH2_ERROR_CHANNEL_CLOSED - The channel has been closed.

       libssh2_channel_read_ex - read data from a channel stream

       Actual  number  of  bytes  read  or  negative  on  failure. It returns LIBSSH2_ERROR_EAGAIN when it would
       otherwise block. While LIBSSH2_ERROR_EAGAIN is a negative number, it is not really a failure per se.

       Note that a return value of zero (0) can in fact be a legitimate value and only signals that  no  payload
       data was read. It is not an error.

libssh2_poll_channel_read(3)

libssh2 0.15                                       1 Jun 2007                         libssh2_channel_read_ex(3)

       #include <libssh2.h>

       ssize_t
       libssh2_channel_read_ex(LIBSSH2_CHANNEL *channel, int stream_id,
                               char *buf, size_t buflen);

       ssize_t
       libssh2_channel_read(LIBSSH2_CHANNEL *channel,
                            char *buf, size_t buflen);

       ssize_t
       libssh2_channel_read_stderr(LIBSSH2_CHANNEL *channel,
                                   char *buf, size_t buflen);