error while compiling :

["Ankur Bhargava" <bhargava_ankur@xxxxxxxxxxx>]

Hi ,
when i do make in the libimage directory of the untarred src i get error:
_XOPEN_SOURCE not supported . if i remove this flag -D_XOPEN_SOURCE from the
ivcommondefs file.line no: 33 : LINUXDEFS = -DPOSIX_SOURCE -D_XOPEN_SOURCE
the source compiles without any warnings..i have no idea what this flag
does. is it ok to compile without this flag ? why is this flag included. ?

am using gcc compiler version 2.95.2.

thanks,
ankur