--- parser3/src/include/pa_os.h	2003/11/06 08:50:26	1.1
+++ parser3/src/include/pa_os.h	2026/10/02 19:57:10	1.16
@@ -1,21 +1,36 @@
 /** @file
 	Parser: commonly used functions.
 
-	Copyright (c) 2001-2003 ArtLebedev Group (http://www.artlebedev.com)
-	Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
+	Copyright (c) 2001-2026 Art. Lebedev Studio (https://www.artlebedev.com)
+	Authors: Konstantin Morshnev <moko@design.ru>, Alexandr Petrosian <paf@design.ru>
 */
 
 #ifndef PA_OS_H
 #define PA_OS_H
 
-static const char* IDENT_OS_H="$Date: 2003/11/06 08:50:26 $";
+#define IDENT_PA_OS_H "$Id: pa_os.h,v 1.16 2026/10/02 19:57:10 moko Exp $"
+
+#define PA_LOCK_ATTEMPTS 20
+#define PA_LOCK_WAIT_TIMEOUT_SECS 0
+#define PA_LOCK_WAIT_TIMEOUT_USECS 500000
+
+extern unsigned int pa_lock_attempts;
+
+// 'blocking' mean we will wait till other process release lock 
+// but we'll make PA_LOCK_ATTEMPTS attempts with PA_LOCK_WAIT_TIMEOUT secs delaus between attempts 
+// 'nonblocking' mean we will make only 1 attempt without waiting
 
 int pa_lock_shared_blocking(int fd);
 int pa_lock_exclusive_blocking(int fd);
 int pa_lock_exclusive_nonblocking(int fd);
 int pa_unlock(int fd);
 
-/// yields to OS for secs secs and usecs milliseconds
+/// yields to OS for secs secs and usecs microseconds (1E-6)
 int pa_sleep(unsigned long secs, unsigned long usecs);
 
+#ifdef _MSC_VER
+/// sets errno from GetLastError(), as CRT does, if the passed windows api call result is zero; returns it
+int pa_set_errno(int status);
+#endif
+
 #endif