---
name: "mongoc_stream_readv"
section: "3"
platform: "linux"
package: "libmongoc-doc"
version: "1.30.4-1+deb13u3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/mongoc_stream_readv"
---

# mongoc\_stream\_readv(3)

## SYNOPSIS

```
ssize_t
mongoc_stream_readv (mongoc_stream_t *stream,
                     mongoc_iovec_t *iov,
                     size_t iovcnt,
                     size_t min_bytes,
                     int32_t timeout_msec);
```

## PARAMETERS

- •

  **stream**: A *mongoc\_stream\_t*.

- •

  **iov**: A vector of *mongoc\_iovec\_t*.

- •

  **iovcnt**: The number of items in **iov**.

- •

  **min\_bytes**: The minimum number of bytes to read or failure will be indicated.

- •

  **timeout\_msec**: A timeout in milliseconds, or 0 to indicate non-blocking. A negative value with use the default timeout.

This function is identical to *mongoc\_stream\_read()* except that it takes a *mongoc\_iovec\_t* to perform gathered I/O.

**WARNING:**

The "default timeout" indicated by a negative value is both unspecified and unrelated to the documented default values for **\*TimeoutMS** URI options. To specify a default timeout value for a **\*TimeoutMS** URI option, use the **MONGOC\_DEFAULT\_\*** constants defined in **mongoc-client.h**.

## RETURNS

**\>= 0** on success, **-1** on failure and **errno** is set.

**SEE ALSO:**

```
mongoc_stream_read()
```

```
mongoc_stream_write()
```

```
mongoc_stream_writev()
```

## AUTHOR

MongoDB, Inc

## COPYRIGHT

2009-present, MongoDB, Inc.