better version of file.is_writable() from Hans

git-svn-id: svn://tug.org/texlive/trunk@22770 c570f23f-e606-0410-a88d-b1316a301751

24 files changed, 335 insertions, 524 deletions

diff --git a/Build/source/texk/texlive/context/mtxrun b/Build/source/texk/texlive/context/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Build/source/texk/texlive/context/mtxrun
+++ b/Build/source/texk/texlive/context/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/alpha-linux/mtxrun b/Master/bin/alpha-linux/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/alpha-linux/mtxrun
+++ b/Master/bin/alpha-linux/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/amd64-freebsd/mtxrun b/Master/bin/amd64-freebsd/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/amd64-freebsd/mtxrun
+++ b/Master/bin/amd64-freebsd/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/amd64-kfreebsd/mtxrun b/Master/bin/amd64-kfreebsd/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/amd64-kfreebsd/mtxrun
+++ b/Master/bin/amd64-kfreebsd/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/i386-cygwin/mtxrun b/Master/bin/i386-cygwin/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/i386-cygwin/mtxrun
+++ b/Master/bin/i386-cygwin/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/i386-freebsd/mtxrun b/Master/bin/i386-freebsd/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/i386-freebsd/mtxrun
+++ b/Master/bin/i386-freebsd/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/i386-kfreebsd/mtxrun b/Master/bin/i386-kfreebsd/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/i386-kfreebsd/mtxrun
+++ b/Master/bin/i386-kfreebsd/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/i386-linux/mtxrun b/Master/bin/i386-linux/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/i386-linux/mtxrun
+++ b/Master/bin/i386-linux/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/i386-netbsd/mtxrun b/Master/bin/i386-netbsd/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/i386-netbsd/mtxrun
+++ b/Master/bin/i386-netbsd/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/i386-solaris/mtxrun b/Master/bin/i386-solaris/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/i386-solaris/mtxrun
+++ b/Master/bin/i386-solaris/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/mips-irix/mtxrun b/Master/bin/mips-irix/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/mips-irix/mtxrun
+++ b/Master/bin/mips-irix/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/powerpc-aix/mtxrun b/Master/bin/powerpc-aix/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/powerpc-aix/mtxrun
+++ b/Master/bin/powerpc-aix/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/powerpc-linux/mtxrun b/Master/bin/powerpc-linux/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/powerpc-linux/mtxrun
+++ b/Master/bin/powerpc-linux/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/sparc-linux/mtxrun b/Master/bin/sparc-linux/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/sparc-linux/mtxrun
+++ b/Master/bin/sparc-linux/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/sparc-solaris/mtxrun b/Master/bin/sparc-solaris/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/sparc-solaris/mtxrun
+++ b/Master/bin/sparc-solaris/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/universal-darwin/mtxrun b/Master/bin/universal-darwin/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/universal-darwin/mtxrun
+++ b/Master/bin/universal-darwin/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/win32/mtxrun.lua b/Master/bin/win32/mtxrun.lua
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/win32/mtxrun.lua
+++ b/Master/bin/win32/mtxrun.lua
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/x86_64-darwin/mtxrun b/Master/bin/x86_64-darwin/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/x86_64-darwin/mtxrun
+++ b/Master/bin/x86_64-darwin/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/x86_64-linux/mtxrun b/Master/bin/x86_64-linux/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/x86_64-linux/mtxrun
+++ b/Master/bin/x86_64-linux/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/bin/x86_64-solaris/mtxrun b/Master/bin/x86_64-solaris/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/bin/x86_64-solaris/mtxrun
+++ b/Master/bin/x86_64-solaris/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/texmf-dist/scripts/context/lua/mtxrun.lua b/Master/texmf-dist/scripts/context/lua/mtxrun.lua
index 94867f6eb34..29f2eadb437 100755
--- a/Master/texmf-dist/scripts/context/lua/mtxrun.lua
+++ b/Master/texmf-dist/scripts/context/lua/mtxrun.lua
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/texmf-dist/scripts/context/stubs/mswin/mtxrun.lua b/Master/texmf-dist/scripts/context/stubs/mswin/mtxrun.lua
index 94867f6eb34..29f2eadb437 100755
--- a/Master/texmf-dist/scripts/context/stubs/mswin/mtxrun.lua
+++ b/Master/texmf-dist/scripts/context/stubs/mswin/mtxrun.lua
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/texmf-dist/scripts/context/stubs/unix/mtxrun b/Master/texmf-dist/scripts/context/stubs/unix/mtxrun
index 94867f6eb34..29f2eadb437 100755
--- a/Master/texmf-dist/scripts/context/stubs/unix/mtxrun
+++ b/Master/texmf-dist/scripts/context/stubs/unix/mtxrun
@@ -2524,26 +2524,20 @@ end
 
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
@@ -11153,11 +11147,9 @@ resolvers.luacnfname    = 'texmfcnf.lua'
 resolvers.luacnfstate   = "unknown"
 
 -- resolvers.luacnfspec = '{$SELFAUTODIR,$SELFAUTOPARENT}{,{/share,}/texmf{-local,}/web2c}' -- what a rubish path
+resolvers.luacnfspec = 'selfautoparent:{/texmf{-local,}{,/web2c},}}'
+
 
--- changed by Taco Hoekwater to make <root>/texmfnf.lua take precedence,
--- while still allowing <root>/texmf/texmfnf.lua and 
--- <root>/texmf/web2c/texmfnf.lua (in that order)
-resolvers.luacnfspec = '{selfautodir:,selfautoparent:};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,};{selfautodir:,selfautoparent:}{/share,}/texmf{-local,}/web2c'
 
 local unset_variable = "unset"
 
diff --git a/Master/texmf-dist/tex/context/base/l-file.lua b/Master/texmf-dist/tex/context/base/l-file.lua
index 0cc62c730ef..3fea3b0a7c4 100644
--- a/Master/texmf-dist/tex/context/base/l-file.lua
+++ b/Master/texmf-dist/tex/context/base/l-file.lua
@@ -147,30 +147,25 @@ end
 --~ print(file.join("//nas-1","/y"))
 
 function file.is_writable(name)
-    if os.type == "windows" then
-      local a = attributes(name) or attributes(dirname(name,"."))
-      return a and sub(a.permissions,2,2) == "w"
-    end
-    local f
-    local isnew = true
     if lfs.isdir(name) then
-      name = name .. "/mtxtest.txt"
+        name = name .. "/m_t_x_t_e_s_t.tmp"
+        local f = io.open(name,"wb")
+        if f then
+            f:close()
+            os.remove(name)
+            return true
+        end
     else
-      f = io.open(name, "rb");
-      if f then
-         f:close()
-         isnew = false
-      end
-    end
-    f = io.open(name, "wb");
-    if f then
-       f:close()
-       if isnew then os.remove(name) end
-       return true
+        f = io.open(name,"ab")
+        if f then
+            f:close()
+            return true
+        end
     end
     return false
 end
 
+
 function file.is_readable(name)
     local a = attributes(name)
     return a and sub(a.permissions,1,1) == "r"