syscalls

[talg]

• added support for dup/dup3 system calls.
• fcntl support, search for lfi tools in /opt

[zyedidia]

Looks like on the x86-64 machine the test fails with:

stdout:
expected:
fcntl F_DUPFD: original fd=3, dup fd=5
fcntl F_GETFL: fd=3 has flags=0x20001
fcntl F_GETFD: fd=3 has fd_flags=0x0
fcntl F_SETFD: fd=3 now has fd_flags=0x1
fcntl F_DUPFD_CLOEXEC correctly returned error (not supported)
fcntl test passed
got:
fcntl F_DUPFD: original fd=3, dup fd=5
fcntl F_GETFL: fd=3 has flags=0x8001
fcntl F_GETFD: fd=3 has fd_flags=0x0
fcntl F_SETFD: fd=3 now has fd_flags=0x1
fcntl F_DUPFD_CLOEXEC correctly returned error (not supported)
fcntl test passed
stderr:
exit status 1

I think this is expected behavior. Maybe the test should just use asserts and not print the file status flags since those could change depending on the host.