linuxcncrsh: ignore SIGPIPE at startup, not after thread creation
linuxcncrsh: ignore SIGPIPE at startup, not after thread creation

Signal disposition is a process-wide setting, not a thread-specific
setting.  So set the disposition of SIGPIPE once and for all at program
startup, instead of each time a client connects.

mhaberler/machinekit,unseenlaser/machinekit,ikcalB/linuxcnc-mirror,ArcEye/machinekit-testing,EqAfrica/machinekit,kinsamanka/machinekit,strahlex/machinekit,Cid427/machinekit,kinsamanka/machinekit,cdsteinkuehler/MachineKit,araisrobo/machinekit,araisrobo/machinekit,unseenlaser/machinekit,bmwiedemann/linuxcnc-mirror,ArcEye/machinekit-testing,ArcEye/MK-Qt5,mhaberler/machinekit,bobvanderlinden/machinekit,ArcEye/MK-Qt5,unseenlaser/machinekit,aschiffler/linuxcnc,Cid427/machinekit,Cid427/machinekit,araisrobo/machinekit,ArcEye/MK-Qt5,bmwiedemann/linuxcnc-mirror,bobvanderlinden/machinekit,cdsteinkuehler/linuxcnc,RunningLight/machinekit,unseenlaser/machinekit,araisrobo/machinekit,RunningLight/machinekit,strahlex/machinekit,unseenlaser/linuxcnc,cdsteinkuehler/MachineKit,RunningLight/machinekit,ArcEye/machinekit-testing,ArcEye/machinekit-testing,araisrobo/machinekit,ikcalB/linuxcnc-mirror,narogon/linuxcnc,jaguarcat79/ILC-with-LinuxCNC,Cid427/machinekit,kinsamanka/machinekit,ArcEye/machinekit-testing,ArcEye/machinekit-testing,bobvanderlinden/machinekit,RunningLight/machinekit,mhaberler/machinekit,strahlex/machinekit,strahlex/machinekit,bobvanderlinden/machinekit,bobvanderlinden/machinekit,aschiffler/linuxcnc,ArcEye/MK-Qt5,mhaberler/machinekit,bmwiedemann/linuxcnc-mirror,cdsteinkuehler/linuxcnc,cdsteinkuehler/linuxcnc,EqAfrica/machinekit,bmwiedemann/linuxcnc-mirror,bmwiedemann/linuxcnc-mirror,ArcEye/MK-Qt5,RunningLight/machinekit,aschiffler/linuxcnc,unseenlaser/machinekit,araisrobo/machinekit,mhaberler/machinekit,bobvanderlinden/machinekit,bobvanderlinden/machinekit,Cid427/machinekit,araisrobo/machinekit,ikcalB/linuxcnc-mirror,cdsteinkuehler/MachineKit,jaguarcat79/ILC-with-LinuxCNC,cdsteinkuehler/linuxcnc,kinsamanka/machinekit,bmwiedemann/linuxcnc-mirror,narogon/linuxcnc,ikcalB/linuxcnc-mirror,jaguarcat79/ILC-with-LinuxCNC,RunningLight/machinekit,cdsteinkuehler/MachineKit,ikcalB/linuxcnc-mirror,unseenlaser/linuxcnc,cdsteinkuehler/MachineKit,aschiffler/linuxcnc,EqAfrica/machinekit,ikcalB/linuxcnc-mirror,ArcEye/machinekit-testing,EqAfrica/machinekit,unseenlaser/linuxcnc,unseenlaser/machinekit,RunningLight/machinekit,kinsamanka/machinekit,Cid427/machinekit,narogon/linuxcnc,ArcEye/MK-Qt5,mhaberler/machinekit,strahlex/machinekit,cdsteinkuehler/MachineKit,unseenlaser/machinekit,kinsamanka/machinekit,narogon/linuxcnc,unseenlaser/linuxcnc,EqAfrica/machinekit,aschiffler/linuxcnc,mhaberler/machinekit,araisrobo/machinekit,jaguarcat79/ILC-with-LinuxCNC,bobvanderlinden/machinekit,cdsteinkuehler/linuxcnc,araisrobo/machinekit,strahlex/machinekit,mhaberler/machinekit,strahlex/machinekit,narogon/linuxcnc,ArcEye/machinekit-testing,unseenlaser/machinekit,Cid427/machinekit,cdsteinkuehler/linuxcnc,kinsamanka/machinekit,RunningLight/machinekit,bmwiedemann/linuxcnc-mirror,unseenlaser/linuxcnc,EqAfrica/machinekit,kinsamanka/machinekit,ArcEye/MK-Qt5,ArcEye/MK-Qt5,EqAfrica/machinekit,EqAfrica/machinekit,jaguarcat79/ILC-with-LinuxCNC,ikcalB/linuxcnc-mirror,Cid427/machinekit