Check return value of write(2) and print an error if it fails.
Check return value of write(2) and print an error if it fails.

Signed-off-by: Erik Mouw <dad272ae52aa329626c064fc296d350d9bc8512a@nl.linux.org>

brandt/openconnect,nmav/openconnect-mine,liiir1985/openconnect,mtmiller/openconnect,chadcatlett/openconnect,don-johnny/openconnect,neshema/openconnect,lins05/openconnect,mveplus/openconnect-client,cernekee/openconnect,nmav/openconnect-mine,sihde/openconnect,ldx/android_external_openconnect,cernekee/openconnect,liiir1985/openconnect,brandt/openconnect,atyndall/openconnect,mdutton3/OpenConnect,don-johnny/openconnect,mtmiller/openconnect,chadcatlett/openconnect,nmav/openconnect-mine,mveplus/openconnect-client,certik/openconnect,matlockx/openconnect,ldx/android_external_openconnect,sihde/openconnect,mveplus/openconnect-client,lins05/openconnect,certik/openconnect,brandt/openconnect,neshema/openconnect,chadcatlett/openconnect,matlockx/openconnect,matlockx/openconnect,atyndall/openconnect,neshema/openconnect,cernekee/openconnect,atyndall/openconnect,mtmiller/openconnect,matlockx/openconnect,certik/openconnect,mdutton3/OpenConnect,cernekee/openconnect,mveplus/openconnect-client,liiir1985/openconnect,liiir1985/openconnect,neshema/openconnect,mtmiller/openconnect,chadcatlett/openconnect,atyndall/openconnect,lins05/openconnect,brandt/openconnect,nmav/openconnect-mine,don-johnny/openconnect,mdutton3/OpenConnect,don-johnny/openconnect,lins05/openconnect,sihde/openconnect,pbrook/openconnect,pbrook/openconnect