diff --git a/qse/configure b/qse/configure
index 2c233d41..8d01f4a8 100755
--- a/qse/configure
+++ b/qse/configure
@@ -17628,7 +17628,7 @@ _ACEOF
 fi
 done
 
-for ac_func in sysconf prctl fdopendir setrlimit getrlimit
+for ac_func in sysconf prctl fdopendir setrlimit getrlimit getpgid getpgrp
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -19051,6 +19051,24 @@ _ACEOF
 fi
 
 
+ac_fn_c_check_type "$LINENO" "struct timespec" "ac_cv_type_struct_timespec" "#include <sys/types.h>
+	 #ifdef HAVE_TIME_H
+	 #include <time.h>
+	 #endif
+	 #ifdef HAVE_SYS_TIME_H
+	 #include <sys/time.h>
+	 #endif
+"
+if test "x$ac_cv_type_struct_timespec" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_TIMESPEC 1
+_ACEOF
+
+
+fi
+
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for va_copy" >&5
 $as_echo_n "checking for va_copy... " >&6; }
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
diff --git a/qse/configure.ac b/qse/configure.ac
index 603ae36b..58f4298d 100644
--- a/qse/configure.ac
+++ b/qse/configure.ac
@@ -148,7 +148,7 @@ AC_CHECK_FUNCS([lseek64 stat64 fstat64 lstat64 ftruncate64 readdir64 dirfd])
 AC_CHECK_FUNCS([lstat fchmod fsync ftruncate])
 AC_CHECK_FUNCS([timegm timelocal localtime_r gettimeofday settimeofday])
 AC_CHECK_FUNCS([utime utimes futimes lutimes futimens])
-AC_CHECK_FUNCS([sysconf prctl fdopendir setrlimit getrlimit])
+AC_CHECK_FUNCS([sysconf prctl fdopendir setrlimit getrlimit getpgid getpgrp])
 AC_CHECK_FUNCS([backtrace backtrace_symbols])
 AC_CHECK_FUNCS([fork vfork posix_spawn gettid nanosleep select])
 AC_CHECK_FUNCS([makecontext swapcontext getcontext setcontext])
@@ -331,6 +331,15 @@ AC_CHECK_MEMBERS([struct sockaddr_in6.sin6_scope_id], [], [],
 	 #include <sys/socket.h> 
 	 #include <netinet/in.h>])
 
+AC_CHECK_TYPES([struct timespec], [], [],
+	[#include <sys/types.h>
+	 #ifdef HAVE_TIME_H
+	 #include <time.h>
+	 #endif
+	 #ifdef HAVE_SYS_TIME_H
+	 #include <sys/time.h>
+	 #endif])
+
 AC_MSG_CHECKING([for va_copy])
 AC_TRY_LINK(
 	[#include <stdarg.h>],
diff --git a/qse/include/qse/config.h.in b/qse/include/qse/config.h.in
index b04ae2e4..da99d682 100644
--- a/qse/include/qse/config.h.in
+++ b/qse/include/qse/config.h.in
@@ -263,6 +263,12 @@
 /* Define to 1 if you have the `getifaddrs' function. */
 #undef HAVE_GETIFADDRS
 
+/* Define to 1 if you have the `getpgid' function. */
+#undef HAVE_GETPGID
+
+/* Define to 1 if you have the `getpgrp' function. */
+#undef HAVE_GETPGRP
+
 /* Define to 1 if you have the `getrlimit' function. */
 #undef HAVE_GETRLIMIT
 
@@ -602,6 +608,9 @@
 /* Define to 1 if `st_mtim.tv_nsec' is a member of `struct stat'. */
 #undef HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
 
+/* Define to 1 if the system has the type `struct timespec'. */
+#undef HAVE_STRUCT_TIMESPEC
+
 /* Define to 1 if you have the `swapcontext' function. */
 #undef HAVE_SWAPCONTEXT
 
diff --git a/qse/include/qse/macros.h b/qse/include/qse/macros.h
index 92a4f66c..974d47b0 100644
--- a/qse/include/qse/macros.h
+++ b/qse/include/qse/macros.h
@@ -41,7 +41,9 @@
 #	define QSE_INLINE inline
 #	define QSE_HAVE_INLINE
 #elif defined(__GNUC__) && defined(__GNUC_GNU_INLINE__)
-#	define QSE_INLINE /*extern*/ inline
+	/* gcc disables inline when -std=c89 or -ansi is used. 
+	 * so use __inline__ supported by gcc regardless of the options */
+#	define QSE_INLINE /*extern*/ __inline__
 #	define QSE_HAVE_INLINE
 #else
 #	define QSE_INLINE 
@@ -49,7 +51,7 @@
 #endif
 
 #if defined(__GNUC__) && defined(__GNUC_GNU_INLINE__)
-#	define QSE_INLINE_ALWAYS inline __attribute__((__always_inline__))
+#	define QSE_INLINE_ALWAYS __inline__ __attribute__((__always_inline__))
 #	define QSE_HAVE_INLINE_ALWAYS
 #elif defined(_MSC_VER) || (defined(__CC_ARM) || defined(__ARMCC__))
 #	define QSE_INLINE_ALWAYS __forceinline
@@ -60,7 +62,7 @@
 #endif
 
 #if defined(__GNUC__) && defined(__GNUC_GNU_INLINE__)
-#	define QSE_INLINE_NEVER inline __attribute__((__noinline__))
+#	define QSE_INLINE_NEVER __inline__ __attribute__((__noinline__))
 #	define QSE_HAVE_INLINE_NEVER
 #elif (defined(__CC_ARM) || defined(__ARMCC__))
 #	define QSE_INLINE_NEVER __declspec(noinline)
@@ -160,7 +162,9 @@
  * that it does not point to anything.
  */
 #if defined(__cplusplus)
-#	if QSE_SIZEOF_VOID_P == QSE_SIZEOF_INT
+#	if (__cplusplus >= 201103L) /* C++11 */
+#		define QSE_NULL nullptr
+#	elif QSE_SIZEOF_VOID_P == QSE_SIZEOF_INT
 #		define QSE_NULL (0)
 #	elif QSE_SIZEOF_VOID_P == QSE_SIZEOF_LONG
 #		define QSE_NULL (0l)
diff --git a/qse/lib/awk/mod-sys.c b/qse/lib/awk/mod-sys.c
index 75087b38..a0d4cc22 100644
--- a/qse/lib/awk/mod-sys.c
+++ b/qse/lib/awk/mod-sys.c
@@ -146,7 +146,7 @@ static int fnc_kill (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 	return 0;
 }
 
-static int fnc_getpgrp (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
+static int fnc_getpgid (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 {
 	qse_awk_int_t pid;
 	qse_awk_val_t* retv;
@@ -164,7 +164,14 @@ static int fnc_getpgrp (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 	pid = -1;
 
 #else
+	/* TODO: support specifing calling process id other than 0 */
+	#if defined(HAVE_GETPGID)
+	pid = getpgid (0);
+	#elif defined(HAVE_GETPGRP)
 	pid = getpgrp ();
+	#else
+	pid = -1;
+	#endif
 #endif
 
 	retv = qse_awk_rtx_makeintval (rtx, pid);
@@ -679,7 +686,7 @@ static fnctab_t fnctab[] =
 	{ QSE_T("geteuid"),    { { 0, 0, QSE_NULL     }, fnc_geteuid,    0  } },
 	{ QSE_T("getgid"),     { { 0, 0, QSE_NULL     }, fnc_getgid,     0  } },
 	{ QSE_T("getnwifcfg"), { { 3, 3, QSE_T("vvr") }, fnc_getnwifcfg, 0  } },
-	{ QSE_T("getpgrp"),    { { 0, 0, QSE_NULL     }, fnc_getpgrp,    0  } },
+	{ QSE_T("getpgid"),    { { 0, 0, QSE_NULL     }, fnc_getpgid,    0  } },
 	{ QSE_T("getpid"),     { { 0, 0, QSE_NULL     }, fnc_getpid,     0  } },
 	{ QSE_T("getppid"),    { { 0, 0, QSE_NULL     }, fnc_getppid,    0  } },
 	{ QSE_T("gettid"),     { { 0, 0, QSE_NULL     }, fnc_gettid,     0  } },
diff --git a/qse/lib/cmn/fmt-intmax.c b/qse/lib/cmn/fmt-intmax.c
index c8187555..70591094 100644
--- a/qse/lib/cmn/fmt-intmax.c
+++ b/qse/lib/cmn/fmt-intmax.c
@@ -194,7 +194,7 @@ int qse_fmtfltmaxtombs (qse_mchar_t* buf, qse_size_t bufsize, qse_fltmax_t f, qs
  
 	if (len + 1 < bufsize)
 	{
-		buf[len++] = point;  // add decimal point to string
+		buf[len++] = point;  /* add decimal point to string */
 		buf[len] = QSE_MT('\0');
 	}
         
diff --git a/qse/lib/cmn/fs-copy.c b/qse/lib/cmn/fs-copy.c
index 9aaa4811..d999499e 100644
--- a/qse/lib/cmn/fs-copy.c
+++ b/qse/lib/cmn/fs-copy.c
@@ -237,7 +237,7 @@ static int copy_file_in_fs (qse_fs_t* fs, cpfile_t* cpfile)
 
 		if (cpfile->flags & QSE_FS_CPFILE_PRESERVE)
 		{
-		#if defined(HAVE_FUTIMENS)
+		#if defined(HAVE_FUTIMENS) && defined(HAVE_STRUCT_TIMESPEC)
 			struct timespec ts[2];
 		#elif defined(HAVE_FUTIMES)
 			struct timeval tv[2];
@@ -254,7 +254,7 @@ static int copy_file_in_fs (qse_fs_t* fs, cpfile_t* cpfile)
 				goto oops;
 			}
 
-		#if defined(HAVE_FUTIMENS)
+		#if defined(HAVE_FUTIMENS) && defined(HAVE_STRUCT_TIMESPEC)
 
 			QSE_MEMSET (&ts, 0, QSE_SIZEOF(ts));
 			ts[0].tv_sec = cpfile->src_attr.atime.sec;
diff --git a/qse/lib/cmn/fs.c b/qse/lib/cmn/fs.c
index 2f1c60de..e90f028f 100644
--- a/qse/lib/cmn/fs.c
+++ b/qse/lib/cmn/fs.c
@@ -645,7 +645,7 @@ qse_fs_ent_t* qse_fs_read (qse_fs_t* fs, int flags)
 
 	if (flags & QSE_FS_ENT_TYPE)
 	{
-	#if defined(HAVE_STRUCT_DIRENT_D_TYPE)
+	#if defined(HAVE_STRUCT_DIRENT_D_TYPE) && defined(DT_DIR) && defined(DT_REG) /* and more */
 		switch (ent->d_type)
 		{
 			case DT_DIR:
@@ -678,18 +678,26 @@ qse_fs_ent_t* qse_fs_read (qse_fs_t* fs, int flags)
 			default:
 				fs->ent.type = QSE_FS_ENT_UNKNOWN;
 				break;
-		}	
+		}
 
 	#else
+		#if defined(__S_IFMT) && !defined(S_IFMT)
+		#	define S_IFMT __S_IFMT
+		#endif
+		#if defined(__S_IFDIR) && !defined(S_IFDIR)
+		#	define S_IFDIR __S_IFDIR
+		#endif
 		#define IS_TYPE(st,type) ((st.st_mode & S_IFMT) == S_IFDIR)
 		fs->ent.type = IS_TYPE(st,S_IFDIR)?  QSE_FS_ENT_SUBDIR:
-		                IS_TYPE(st,S_IFREG)?  QSE_FS_ENT_REGULAR:
-		                IS_TYPE(st,S_IFLNK)?  QSE_FS_ENT_SYMLINK:
-		                IS_TYPE(st,S_IFCHR)?  QSE_FS_ENT_CHRDEV:
-		                IS_TYPE(st,S_IFBLK)?  QSE_FS_ENT_BLKDEV:
-		                IS_TYPE(st,S_IFIFO)?  QSE_FS_ENT_PIPE:
-		                IS_TYPE(st,S_IFSOCK)? QSE_FS_ENT_PIPE:
-		                                      QSE_FS_ENT_UNKNOWN;
+		               IS_TYPE(st,S_IFREG)?  QSE_FS_ENT_REGULAR:
+		               IS_TYPE(st,S_IFLNK)?  QSE_FS_ENT_SYMLINK:
+		               IS_TYPE(st,S_IFCHR)?  QSE_FS_ENT_CHRDEV:
+		               IS_TYPE(st,S_IFBLK)?  QSE_FS_ENT_BLKDEV:
+		               IS_TYPE(st,S_IFIFO)?  QSE_FS_ENT_PIPE:
+		#if defined(S_IFSOCK)
+		               IS_TYPE(st,S_IFSOCK)? QSE_FS_ENT_PIPE:
+		#endif
+		                                     QSE_FS_ENT_UNKNOWN;
 		#undef IS_TYPE
 	#endif
 		fs->ent.flags |= QSE_FS_ENT_TYPE;