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+[[!meta copyright="Copyright © 2011, 2012 Free Software Foundation, Inc."]]
+
+[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
+id="license" text="Permission is granted to copy, distribute and/or modify this
+document under the terms of the GNU Free Documentation License, Version 1.2 or
+any later version published by the Free Software Foundation; with no Invariant
+Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
+is included in the section entitled [[GNU Free Documentation
+License|/fdl]]."]]"""]]
+
+[[!tag open_issue_glibc]]
+
+# IRC, freenode, #hurd, 2011-12-14
+
+    <pinotree> hm, interesting mmap bug
+    <youpi> ?
+    <pinotree> youpi: http://paste.debian.net/149252/
+    #include <sys/types.h>
+    #include <sys/mman.h>
+    #include <fcntl.h>
+    #include <stdio.h>
+    #include <errno.h>
+    #include <stdlib.h>
+    #include <string.h>
+    #include <unistd.h>
+    
+    void die(int x, const char *s)
+    {
+      perror(s);
+      exit(x);
+    }
+    
+    static const char s_file[] = "foo-mmaptest";
+    
+    int main()
+    {
+      int fd;
+      void *p;
+    
+      fd = creat(s_file, 0777);
+      if (fd < 0) die(1, "creat");
+      errno = 0;
+      p = mmap(NULL, 1, PROT_READ, MAP_SHARED, fd, 0);
+      printf("> %p vs %p, %d (%s)\n", p, MAP_FAILED, errno, strerror(errno));
+      unlink(s_file);
+      return (p != MAP_FAILED);
+    }
+    <pinotree> on linux it returns 0 and fails with EACCESS (as it seems it
+      should, by reading the mmap posix docs), on hurd it returns 1 and the
+      mmap succeeds
+    <pinotree> (taken from llvm's configure)
+    <youpi> why should it? file size extension ?
+    <pinotree> creat creates a o_wronly file, while the mmap specifies only
+      read protection
+    <youpi> oh, craet is always wo
+    <youpi> I didn't know that