diff --git a/FileUtils.cpp b/FileUtils.cpp
index b3bcdffb..ffda3cf3 100644
--- a/FileUtils.cpp
+++ b/FileUtils.cpp
@@ -236,8 +236,8 @@ bool CFile::Chmod(const CString& sFile, mode_t mode) {
 	return (chmod(sFile.c_str(), mode) == 0);
 }
 
-bool CFile::Seek(unsigned long uPos) {
-	if (m_iFD != -1 && (unsigned int) lseek(m_iFD, uPos, SEEK_SET) == uPos) {
+bool CFile::Seek(off_t uPos) {
+	if (m_iFD != -1 && lseek(m_iFD, uPos, SEEK_SET) == uPos) {
 		ClearBuffer();
 		return true;
 	}
diff --git a/FileUtils.h b/FileUtils.h
index 4200c96a..1c256408 100644
--- a/FileUtils.h
+++ b/FileUtils.h
@@ -96,7 +96,7 @@ public:
 	static bool Copy(const CString& sOldFileName, const CString& sNewFileName, bool bOverwrite = false);
 	bool Chmod(mode_t mode);
 	static bool Chmod(const CString& sFile, mode_t mode);
-	bool Seek(unsigned long uPos);
+	bool Seek(off_t uPos);
 	bool Truncate();
 	bool Sync();
 	bool Open(const CString& sFileName, int iFlags = O_RDONLY, mode_t iMode = 0644);