On 2021-02-11 19:06, Ken Brown via Cygwin wrote:
On 2/11/2021 10:23 AM, Patrick Chkoreff wrote:
I'm trying to use setrlimit to impose limits on various resources such
as CPU time and memory. The call to setrlimit always fails. I've
distilled this into the following example test.c:
[...]
if (setrlimit(RLIMIT_CPU,&rlim) < 0)
[...]
setrlimit: Invalid argument
Cygwin's setrlimit only supports a few resources, as you can see in the source:
https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/cygwin/resource.cc;h=97777e9d223466b7635b990d6c9e0bfb9e2e9a46;hb=HEAD#l201
In that case could I suggest:
/usr/share/doc/cygwin-doc/html/cygwin-api/compatibility.html#std-susv4
https://cygwin.com/cygwin-api/compatibility.html#std-susv4
in https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/doc/posix.xml
get/setrlimit entries should be annotated with:
(see chapter "Implementation Notes")
and all those entries should be links to "std-notes":
/usr/share/doc/cygwin-doc/html/cygwin-api/std-notes.html
https://cygwin.com/cygwin-api/std-notes.html
<ulink url="std-notes.html">(see chapter "Implementation Notes")</ulink>
in https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/doc/posix.xml
which should have an entry documenting the limitations of get/setrlimit like
e.g.
"<para><function>getrlimit</function> resources RLIMIT_AS, RLIMIT_CPU,
RLIMIT_FSIZE, RLIMIT_DATA always return rlim_cur and rlim_max as RLIM_INFINITY,
so <function>setrlimit</function> returns -1 and sets EINVAL if they are
lowered, or returns 0 if unchanged.
<function>getrlimit</function> resource RLIMIT_NOFILE always returns rlim_cur
and rlim_max as OPEN_MAX; <function>setrlimit</function> returns 0 sets EINVAL
if rlim_cur > rlim_max, does not change the value if it is RLIM_INFINITY,
otherwise returns the result from <function>setdtablesize</function>.
<function>getrlimit</function>/<function>setrlimit</function> resources
RLIMIT_CORE and RLIMIT_STACK return the current values and set the requested values.
All other resource arguments return -1 and set EINVAL.</para>"
--
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada
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