Framing rules make it impractical to implement http/2 correctly on a single blocking thread. The flow-control features introduce feedback between reads and writes, requiring writes to acknowledge reads and reads to throttle writes.

In OkHttp we expose a blocking API over a framed protocol. This document explains the code and policy that makes that work.

### Threads

#### Application's calling thread

}

var errUnreadByte = errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")

// UnreadByte unreads the last byte returned by the most recent successful
// read operation that read at least one byte. If a write has happened since
// the last read, if the last read returned an error, or if the read read zero
// bytes, UnreadByte returns an error.
func (b *Buffer) UnreadByte() error {

        // Decode to new instance (decode reads 36 bytes, encode writes 40)
        FileBasicInfo decoded = new FileBasicInfo();
        int decodedBytes = decoded.decode(buffer, 0, 36);

        // Verify encoding/decoding
        assertEquals(40, encodedBytes); // encode writes 40 bytes (includes padding)
        assertEquals(36, decodedBytes); // decode reads 36 bytes (no padding)

     * @throws IOException If the metadata could not be deserialized.
     * @throws MetadataParseException If the input format could not be parsed.
     */
    Metadata read(File input, Map<String, ?> options) throws IOException, MetadataParseException;

    /**
     * Reads the metadata from the specified character reader. The reader will be automatically closed before the method
     * returns.
     *

# Erasure code sizing guide

## Toy Setups

Capacity constrained environments, MinIO will work but not recommended for production.

| servers | drives (per node) | stripe_size | parity chosen (default) | tolerance for reads (servers) | tolerance for writes (servers) |
|--------:|------------------:|------------:|------------------------:|------------------------------:|-------------------------------:|

		c.Conn.SetWriteDeadline(now.Add(c.writeDeadline + updateInterval))
		c.writeSetAt = now
	}
}

// Read - reads data from the connection using wrapped buffered reader.
func (c *DeadlineConn) Read(b []byte) (n int, err error) {
	if c.abortReads.Load() {
		return 0, context.DeadlineExceeded
	}
	c.setReadDeadline()
	n, err = c.Conn.Read(b)
	return n, err
}

// Write - writes data to the connection.

     * @throws IOException If the settings could not be deserialized.
     * @throws SettingsParseException If the input format could not be parsed.
     */
    Settings read(File input, Map<String, ?> options) throws IOException, SettingsParseException;

    /**
     * Reads the settings from the specified character reader. The reader will be automatically closed before the method
     * returns.
     *

     * @throws ToolchainsParseException If the input format could not be parsed.
     */
    PersistedToolchains read(File input, Map<String, ?> options) throws IOException, ToolchainsParseException;

    /**
     * Reads the toolchains from the specified character reader. The reader will be automatically closed before the
     * method returns.
     *

	}
	if vals := strings.Split(key.Name, "."); len(vals) == 2 {
		key.Extension = "." + vals[1]
		key.Name = strings.TrimSuffix(key.Name, key.Extension)
	}
	return key
}

// replayItems - Reads the items from the store and replays.
func replayItems[I any](store Store[I], doneCh <-chan struct{}, log logger, id string) <-chan Key {
	keyCh := make(chan Key)

	go func() {
		defer xioutil.SafeClose(keyCh)

// A HardLimitedReader reads from R but limits the amount of
// data returned to just N bytes. Each call to Read
// updates N to reflect the new amount remaining.
// Read returns EOF when N <= 0 or when the underlying R returns EOF.
type HardLimitedReader struct {
	R io.Reader // underlying reader
	N int64     // max bytes remaining
}

func (l *HardLimitedReader) Read(p []byte) (n int, err error) {
	if l.N < 0 {