Gnulib module: dup2 or dup2-obsolete
Portability problems fixed by either Gnulib module
EINVALwhen duplicating an fd to itself: Android.
FD_CLOEXECflag when duplicating an fd to itself on some platforms: Haiku.
dup2 (1, 1)on some platforms: Cygwin 1.5.x.
-1on some platforms: Linux releases between July 2008 and May 2009 (versions 2.6.27 to 2.6.29).
EBADFfor large targets, which interferes with using
dup2(fd,fd)==fd)as the minimal
EBADFfilter: AIX 7.1, FreeBSD 6.1, Cygwin 1.5.
Portability problems fixed by Gnulib module
Portability problems not fixed by Gnulib: