---
name: "LockFileEx"
section: "3w"
platform: "linux"
package: "libwine-dev"
version: "1.4.1-4"
release: "Debian 7 (Wheezy)"
platforms: ["linux"]
url: "https://new.carta.tech/LockFileEx"
---

# LockFileEx(3w)

## NAME

**LockFileEx** (KERNEL32.@)

## SYNOPSIS

BOOL LockFileEx\
  (\
   HANDLE       *hFile*,\
   DWORD        *flags*,\
   DWORD        *reserved*,\
   DWORD        *count\_low*,\
   DWORD        *count\_high*,\
   LPOVERLAPPED *overlapped*\
  )

## DESCRIPTION

Locks a byte range within an open file for shared or exclusive access.

## RETURNS

**success:** **TRUE**

**failure:** **FALSE**.

## NOTES

Per Microsoft(tm) docs, the third parameter (*reserved*) must be set to **0.**

## IMPLEMENTATION

Declared in **"winbase.h"**.

Implemented in **"dlls/kernel32/file.c"**.

Debug channel **"file"**.