Hi, I try follow, # virsh vcpupin guest_dom AAA 0,1 [no error messages] # echo $? 1 There is no processing to output an error-message, when vshCommandOptInt become an error. I make the patch to solve this problem. Thanks, Shigeki Sakamoto. Index: src/virsh.c =================================================================== RCS file: /data/cvs/libvirt/src/virsh.c,v retrieving revision 1.134 diff -u -p -r1.134 virsh.c --- src/virsh.c 27 Feb 2008 16:14:44 -0000 1.134 +++ src/virsh.c 4 Mar 2008 08:35:47 -0000 @@ -1723,6 +1723,8 @@ cmdVcpupin(vshControl * ctl, vshCmd * cm vcpu = vshCommandOptInt(cmd, "vcpu", &vcpufound); if (!vcpufound) { + vshCmdOpt *arg = vshCommandOpt(cmd, "vcpu"); + vshError(ctl, FALSE, _("vcpu: %s: Invalid virtual CPU number."), arg->data); virDomainFree(dom); return FALSE; }