diff --git a/config/lyxinclude.m4 b/config/lyxinclude.m4
index 05a69d6c8e..c742c2eb25 100644
--- a/config/lyxinclude.m4
+++ b/config/lyxinclude.m4
@@ -571,6 +571,26 @@ do
       [AC_MSG_RESULT(no)])
 done])
 
+dnl this is used by the macro below to generate a proper config.h.in entry
+m4_define([LYX_AH_CHECK_DEF],
+[AH_TEMPLATE(AS_TR_CPP(HAVE_DEF_$1),
+  [Define to 1 if `$1' is defined in `$2'])])
+
+dnl Check whether name is defined in header by using it in codesnippet.
+dnl Called like LYX_CHECK_DEF(name, header, codesnippet)
+dnl Defines HAVE_DEF_{NAME}
+AC_DEFUN([LYX_CHECK_DEF],
+[LYX_AH_CHECK_DEF($1, $2)
+ AC_MSG_CHECKING([if $1 is defined by header $2])
+ AC_TRY_COMPILE([#include <$2>], [$3],
+     lyx_have_def_name=yes,
+     lyx_have_def_name=no)
+ AC_MSG_RESULT($lyx_have_def_name)
+ if test "x$lyx_have_def_name" = xyes; then
+   AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_DEF_$1))
+ fi
+])
+
 dnl Extract the single digits from PACKAGE_VERSION and make them available.
 dnl Defines LYX_MAJOR_VERSION, LYX_MINOR_VERSION, LYX_RELEASE_LEVEL,
 dnl LYX_RELEASE_PATCH (possibly equal to 0), LYX_DIR_VER, and LYX_USERDIR_VER.
diff --git a/configure.ac b/configure.ac
index c8fac2fca0..2f7680d105 100644
--- a/configure.ac
+++ b/configure.ac
@@ -183,6 +183,8 @@ AC_TYPE_SIGNAL
 AC_TYPE_SIZE_T
 AC_TYPE_UID_T
 
+LYX_CHECK_DEF(PATH_MAX, limits.h, [int n = PATH_MAX;])
+
 AC_CHECK_FUNCS(chmod close _close fork getpid _getpid lstat mkfifo open _open pclose _pclose popen _popen readlink strerror)
 # Check the form of mkdir()
 AC_FUNC_MKDIR
diff --git a/src/support/os_unix.cpp b/src/support/os_unix.cpp
index 9663d98b64..20a6316fde 100644
--- a/src/support/os_unix.cpp
+++ b/src/support/os_unix.cpp
@@ -297,15 +297,15 @@ bool autoOpenFile(string const & filename, auto_open_mode const mode)
 
 string real_path(string const & path)
 {
-#ifdef __GLIBC__
+#ifdef HAVE_DEF_PATH_MAX
+	char rpath[PATH_MAX + 1];
+	char * result = realpath(path.c_str(), rpath);
+	return FileName::fromFilesystemEncoding(result ? rpath : path).absFileName();
+#else
 	char * result = realpath(path.c_str(), NULL);
 	string ret = FileName::fromFilesystemEncoding(result ? result : path).absFileName();
 	free(result);
 	return ret;
-#else
-	char rpath[PATH_MAX + 1];
-	char * result = realpath(path.c_str(), rpath);
-	return FileName::fromFilesystemEncoding(result ? rpath : path).absFileName();
 #endif
 }