Subject: Re: increase default for number of files descriptors per process (was Re: Speeding up "pstat -T")
To: Jun-ichiro itojun Hagino <>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
List: tech-userlevel
Date: 10/07/2003 11:17:06
>        you can change FD_SETSIZE without libc shlib major bump.

No, in fact we cannot, as libc has some on-stack fd-set masks sized
for the *default* FD_SETSIZE, which are exposed further up the API and
ABI.  Increasing the default FD_SETSIZE will change that ABI in a
non-backward compatible way.

(If memory serves, the affected routines are somewhwere in the rpc
code; try "man 3 rpc" looking for fd_set, maybe svc_fdset.  We went over
this in detail some years back; you could try checking the archives.)