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# zx_socket_read
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Read data from a socket.
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#include <zircon/syscalls.h>
zx_status_t zx_socket_read(zx_handle_t handle,
uint32_t options,
void* buffer,
size_t buffer_size,
size_t* actual);
`zx_socket_read()` attempts to read *buffer_size* bytes into *buffer*. If
successful, the number of bytes actually read are return via
If a NULL *actual* is passed in, it will be ignored.
If the socket was created with **ZX_SOCKET_DATAGRAM**, this syscall reads
only the first available datagram in the socket (if one is present).
If *buffer* is too small for the datagram, then the read will be
truncated, and any remaining bytes in the datagram will be discarded.
Supported *options* are:
* **ZX_SOCKET_PEEK** to leave the message in the socket.
To determine how many bytes are available to read, use the **rx_buf_available**
field of the resulting `zx_info_socket_t`, which you can obtain using the
**ZX_INFO_SOCKET** topic for [`zx_object_get_info()`].
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*handle* must be of type **ZX_OBJ_TYPE_SOCKET** and have **ZX_RIGHT_READ**.
`zx_socket_read()` returns **ZX_OK** on success, and writes into
*actual* (if non-NULL) the exact number of bytes read.
**ZX_ERR_BAD_HANDLE** *handle* is not a valid handle.
**ZX_ERR_BAD_STATE** reading has been disabled for this socket endpoint via [`zx_socket_shutdown()`].
**ZX_ERR_WRONG_TYPE** *handle* is not a socket handle.
**ZX_ERR_INVALID_ARGS** If any of *buffer* or *actual* are non-NULL
but invalid pointers, or if *buffer* is NULL, or if *options* is zero.
**ZX_ERR_ACCESS_DENIED** *handle* does not have **ZX_RIGHT_READ**.
**ZX_ERR_SHOULD_WAIT** The socket contained no data to read.
**ZX_ERR_PEER_CLOSED** The other side of the socket is closed and no data is
- [`zx_socket_create()`]
- [`zx_socket_shutdown()`]
- [`zx_socket_write()`]
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