use proper flags for sendmsg() on Unix (#32356)
use proper flags for sendmsg() on Unix (#32356)

* use proper flags

* fix spacing

shimingsg/corefx,wtgodbe/corefx,ViktorHofer/corefx,wtgodbe/corefx,mmitche/corefx,mmitche/corefx,shimingsg/corefx,ericstj/corefx,mmitche/corefx,ptoonen/corefx,Jiayili1/corefx,ViktorHofer/corefx,Jiayili1/corefx,BrennanConroy/corefx,wtgodbe/corefx,Jiayili1/corefx,BrennanConroy/corefx,ViktorHofer/corefx,ptoonen/corefx,shimingsg/corefx,Jiayili1/corefx,mmitche/corefx,shimingsg/corefx,ericstj/corefx,wtgodbe/corefx,ptoonen/corefx,ViktorHofer/corefx,BrennanConroy/corefx,shimingsg/corefx,ptoonen/corefx,ericstj/corefx,mmitche/corefx,wtgodbe/corefx,shimingsg/corefx,ViktorHofer/corefx,wtgodbe/corefx,Jiayili1/corefx,ericstj/corefx,ericstj/corefx,mmitche/corefx,ptoonen/corefx,shimingsg/corefx,ptoonen/corefx,Jiayili1/corefx,ericstj/corefx,ViktorHofer/corefx,ViktorHofer/corefx,wtgodbe/corefx,mmitche/corefx,ericstj/corefx,ptoonen/corefx,Jiayili1/corefx