=====Gestion des messages d'erreur=====
====Warning: invalid file descriptor -1 in syscall XXXXX()====
Il n'y a pas d'information accompagnant ce message. Il faut ''valgrind -v'' pour avoir la pile.

Avant :
<code>
==10962== Warning: invalid file descriptor -1 in syscall write()
</code>

Après :
<code>
==10962== Warning: invalid file descriptor -1 in syscall write()
==10962==    at 0x5B6478D: write (write.c:27)
==10962==    by 0x127FB7: copy_to_buffer (record.c:767)
==10962==    by 0x127FB7: record_mmap_file.isra.9 (record.c:817)
==10962==    by 0x129F0A: flush_shmem_list (record.c:863)
==10962==    by 0x129F0A: finish_writers (record.c:1804)
==10962==    by 0x129F0A: do_main_loop (record.c:1895)
==10962==    by 0x12B397: command_record (record.c:1969)
==10962==    by 0x118E4D: command_live (live.c:129)
==10962==    by 0x1124E8: main (uftrace.c:1050)
</code>