ftruncate and sigsetmask for SysV?

[Guy Harris]

>has anyone produced versions of the BSD functions ftruncate() and
>sigsetmask() for SysV, in particular for the 3b1? any pointers as to
>where these could be found would be helpful. alternatively, are there
>any SysV equivalent approaches?

There is no fully-functional equivalent to "ftruncate()" in any flavor
of vanilla S5, which makes it unlikely that anybody's produced a version
of them for S5 - the hooks just aren't there.  "sigsetmask" also
requires a more powerful signal mechanism than existed prior to S5R3; it
might be possible to do some or all of "sigsetmask" atop S5R3, but it's
not posssible to do it atop the signal mechanism that existed prior to
that.