In commit b46c4787dde79b015dad67dedda4ccf6ff1a3082 I changed the code to watch long running jobs in virsh. Unfortunately I didn't take into account that poll may get a hangup if the terminal is not a TTY and will be closed. This patch avoids polling the STDIN fd when there's no TTY. --- tools/virsh-domain.c | 7 ++++++- tools/virsh.c | 7 +++++++ tools/virsh.h | 2 ++ 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c index b75f331..5aabccd 100644 --- a/tools/virsh-domain.c +++ b/tools/virsh-domain.c @@ -3529,6 +3529,7 @@ vshWatchJob(vshControl *ctl, bool functionReturn = false; sigset_t sigmask, oldsigmask; bool jobStarted = false; + nfds_t npollfd = 2; sigemptyset(&sigmask); sigaddset(&sigmask, SIGINT); @@ -3539,9 +3540,13 @@ vshWatchJob(vshControl *ctl, sigemptyset(&sig_action.sa_mask); sigaction(SIGINT, &sig_action, &old_sig_action); + /* don't poll on STDIN if we are not using a terminal */ + if (!vshTTYAvailable(ctl)) + npollfd = 1; + GETTIMEOFDAY(&start); while (1) { - ret = poll((struct pollfd *)&pollfd, 2, 500); + ret = poll((struct pollfd *)&pollfd, npollfd, 500); if (ret > 0) { if (pollfd[1].revents & POLLIN && saferead(STDIN_FILENO, &retchar, sizeof(retchar)) > 0) { diff --git a/tools/virsh.c b/tools/virsh.c index a76229a..8425f53 100644 --- a/tools/virsh.c +++ b/tools/virsh.c @@ -2226,6 +2226,13 @@ vshTTYIsInterruptCharacter(vshControl *ctl ATTRIBUTE_UNUSED, } +bool +vshTTYAvailable(vshControl *ctl) +{ + return ctl->istty; +} + + int vshTTYDisableInterrupt(vshControl *ctl ATTRIBUTE_UNUSED) { diff --git a/tools/virsh.h b/tools/virsh.h index f978d94..b843788 100644 --- a/tools/virsh.h +++ b/tools/virsh.h @@ -365,6 +365,8 @@ bool vshTTYIsInterruptCharacter(vshControl *ctl, const char chr); int vshTTYDisableInterrupt(vshControl *ctl); int vshTTYRestore(vshControl *ctl); int vshTTYMakeRaw(vshControl *ctl, bool report_errors); +bool vshTTYAvailable(vshControl *ctl); + /* allocation wrappers */ void *_vshMalloc(vshControl *ctl, size_t sz, const char *filename, int line); -- 1.8.3.2