Question on posix_dir in

Jeff Johnston
Tue Oct 2 20:20:00 GMT 2012

There is no: "you should set posix_dir".  The libc/posix directory has 
optional functions to add to the library.  These functions are not C89 
standard and come from the Posix standard.  They may require syscalls in 
addition to the minimal set for newlib platforms (e.g. popen requires 
pipe()).  Many of the embedded platforms only support the minimal 
syscall set via libgloss.

So, if your system has those extra syscalls implemented and you want to 
add some of those Posix functions for your end-users, then enable them 
to build.  You can exclude various functions there via compile flags in 
the case where you support some of the required syscalls but not all.

Cygwin is interested in supplying these functions and has the syscalls 
to support them so they enable them into their build of newlib.

-- Jeff J.

On 09/25/2012 11:49 PM, Can Finner wrote:
> Hi,
> I noticed that posix_dir is set for some targets like cygwin/x86, but
> not other targets. I don't understand very well when should we set
> posix_dir. Could somebody give me some background information about
> this?
> Thanks very much.

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