diff --git a/lib/ulib/support/cgilsxml.py b/lib/ulib/support/cgilsxml.py
index a8d783c..b74b567 100755
--- a/lib/ulib/support/cgilsxml.py
+++ b/lib/ulib/support/cgilsxml.py
@@ -143,7 +143,7 @@ class File:
 
     def __init__(self, dir=None, name=None, pf=None, dontlist=False):
         if pf is None:
-            if dir is None or name is None: raise ValueError("either dir/name or pf must be specified")
+            if dir is None or name is None: raise ValueError("either (dir,name) or pf must be specified")
             pf = path.join(dir, name)
         dir, name =  path.split(pf) # il est possible que name soit de la forme subdir/name
         dir = path.abspath(dir)
@@ -186,7 +186,10 @@ def find_files(basedir, filters):
     if deep_filters:
         for dirpath, dirnames, filenames in os.walk(basedir):
             for filename in filenames:
-                file = File(dirpath, filename)
+                # race condition: si le fichier disparait entre-temps, une
+                # exception se produit
+                try: file = File(dirpath, filename)
+                except: continue
                 matched = False
                 allowed = False
                 for filter in deep_filters:
@@ -199,7 +202,10 @@ def find_files(basedir, filters):
     simple_filters = [filter for filter in filters if filter.re_spec is not None and not filter.deep_scan]
     if simple_filters:
         for name in os.listdir(basedir):
-            file = File(basedir, name)
+            # race condition: si le fichier disparait entre-temps, une
+            # exception se produit
+            try: file = File(basedir, name)
+            except: continue
             if not file.isfile(): continue
             matched = False
             allowed = False
@@ -213,10 +219,21 @@ def find_files(basedir, filters):
     glob_filters = [filter for filter in filters if filter.glob is not None]
     if glob_filters:
         for filter in glob_filters:
+            candidates = []
             if filter.deep_scan:
-                candidates = [File(pf=pf) for pf in glob.glob(path.join(basedir, filter.glob))]
+                for pf in glob.glob(path.join(basedir, filter.glob)):
+                    # race condition: si le fichier disparait entre-temps, une
+                    # exception se produit
+                    try: file = File(pf=pf)
+                    except: continue
+                    candidates.append(file)
             else:
-                candidates = [File(basedir, name) for name in os.listdir(basedir)]
+                for name in os.listdir(basedir):
+                    # race condition: si le fichier disparait entre-temps, une
+                    # exception se produit
+                    try: file = File(basedir, name)
+                    except: continue
+                    candidates.append(file)
             for file in candidates:
                 if not file.isfile(): continue
                 elif filter.match_fill(file): pass