// Package lock - implements filesystem locking wrappers around an
// open file descriptor.
package lock

import (
	"errors"
	"os"
	"sync"
)

// ErrAlreadyLocked is returned if the underlying fd is already locked.
var ErrAlreadyLocked = errors.New("file already locked")

// RLockedFile represents a read locked file, implements a special

// lineTooLong is generated as chunk header is bigger than 4KiB.
var errLineTooLong = errors.New("header line too long")

// malformed encoding is generated when chunk header is wrongly formed.
var errMalformedEncoding = errors.New("malformed chunked encoding")

// chunk is considered too big if its bigger than > 16MiB.
var errChunkTooBig = errors.New("chunk too big: choose chunk size <= 16MiB")

* **`400 - 499`** are for "Client error" responses. These are the second type you would probably use the most.
    * An example is `404`, for a "Not Found" response.
    * For generic errors from the client, you can just use `400`.

        logging.error(
            f"Response was not 200, after: {after}, category_id: {category_id}"
        )
        logging.error(response.text)
        raise RuntimeError(response.text)
    data = response.json()
    if "errors" in data:
        logging.error(f"Errors in response, after: {after}, category_id: {category_id}")
        logging.error(data["errors"])
        logging.error(response.text)

	if m.status == scanStateStarted && time.Since(m.lastHandout) > metacacheMaxClientWait {
		// Drop if client hasn't been seen for 3 minutes.
		m.status = scanStateError
		m.error = "client not seen"
	}

	if m.error == "" && update.error != "" {
		m.error = update.error
		m.status = scanStateError
		m.ended = now
	}
	m.fileNotFound = m.fileNotFound || update.fileNotFound
}

// delete all cache data on disks.

func NewParquetReader(rsc io.ReadSeekCloser, _ *ReaderArgs) (r *Reader, err error) {
	fr, err := parquetgo.NewFileReader(rsc)
	if err != nil {
		return nil, errParquetParsingError(err)
	}

	return &Reader{Closer: rsc, r: fr}, nil
}

func (pr *Reader) Read(dst sql.Record) (rec sql.Record, rerr error) {
	nextRow, err := pr.r.NextRow()
	if err != nil {
		if err == io.EOF {
			return nil, err
		}

- ✅ Clear exception messages

### 3. Error Handling
- ✅ Archive extractors continue on partial failures
- ✅ Processing statistics in error messages
- ✅ Specific file names in error logs

### 4. Error Messages
- ✅ Encoding information in TextExtractor errors
- ✅ File type context in MS Office errors
- ✅ Archive type in archive extractor errors

## Testing Best Practices

package dns

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"net"
	"sort"
	"strings"
	"time"

	"github.com/minio/minio-go/v7/pkg/set"
	clientv3 "go.etcd.io/etcd/client/v3"
)

// ErrNoEntriesFound - Indicates no entries were found for the given key (directory)
var ErrNoEntriesFound = errors.New("No entries found for this key")

// ErrDomainMissing - Indicates domain is missing

package main

import (
	"encoding/binary"
	"errors"
	"flag"
	"fmt"
	"log"
	"os"

	"github.com/olekukonko/tablewriter"
	"github.com/pkg/xattr"
)

var (
	path, name string
	value      uint64
	set, list  bool
)

func getxattr(path, name string) (uint64, error) {
	buf, err := xattr.LGet(path, name)
	if err != nil {
		return 0, err
	}

		if m.Port == "" {
			return fmt.Errorf("unspecified port")
		}
		if _, err := strconv.Atoi(m.Port); err != nil {
			return fmt.Errorf("invalid port")
		}
		if m.Database == "" {
			return fmt.Errorf("database unspecified")
		}
	}

	if m.QueueDir != "" {
		if !filepath.IsAbs(m.QueueDir) {
			return errors.New("queueDir path should be absolute")
		}
	}