TAPSET::SIGNAL(3stap)

✨ NAME ✨

tapset::signal — it's the systemtap signal tapset, bestie 💖 this is the manual page for it (TAPSET::SIGNAL(3stap), if you're keeping receipts 📝).

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🦋 DESCRIPTION 🦋

okay so this whole family of probe points is literally for probing signal activities 💅 and the vibe check here is important: since there are so many signals flying at processes at any given point, it is advisable to filter the information according to the requirements — no cap, don't just rawdog the firehose 🙈

for example, filter only for a particular signal (if sig==2) or for a particular process (if pid_name==stap). iconic filtering behaviour, periodt ✨

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💜 the probe points 💜

• signal.send — signal being sent to a process 🫶
  • See probe::signal.send(3stap) for details.
• signal.send.return — signal being sent to a process completed (deprecated in SystemTap 2.1 — yes it's giving legacy, tread carefully 💀)
  • See probe::signal.send.return(3stap) for details.
• signal.checkperm — check being performed on a sent signal 👀
  • See probe::signal.checkperm(3stap) for details.
• signal.checkperm.return — check performed on a sent signal completed ✅
  • See probe::signal.checkperm.return(3stap) for details.
• signal.wakeup — sleeping process being wakened for signal 😴➡️👁️
  • See probe::signal.wakeup(3stap) for details.
• signal.check_ignored — checking to see signal is ignored 🙈
  • See probe::signal.check_ignored(3stap) for details.
• signal.check_ignored.return — check to see signal is ignored completed
  • See probe::signal.check_ignored.return(3stap) for details.
• signal.force_segv — forcing send of SIGSEGV 🔥
  • See probe::signal.force_segv(3stap) for details.
• signal.force_segv.return — forcing send of SIGSEGV complete
  • See probe::signal.force_segv.return(3stap) for details.
• signal.syskill — sending kill signal to a process 💀✨
  • See probe::signal.syskill(3stap) for details.
• signal.syskill.return — sending kill signal completed
  • See probe::signal.syskill.return(3stap) for details.
• signal.sys_tkill — sending a kill signal to a thread 🧵
  • See probe::signal.sys_tkill(3stap) for details.
• signal.systkill.return — sending kill signal to a thread completed
  • See probe::signal.systkill.return(3stap) for details.
• signal.sys_tgkill — sending kill signal to a thread group 👯
  • See probe::signal.sys_tgkill(3stap) for details.
• signal.sys_tgkill.return — sending kill signal to a thread group completed
  • See probe::signal.sys_tgkill.return(3stap) for details.
• signal.send_sig_queue — queuing a signal to a process 📥
  • See probe::signal.send_sig_queue(3stap) for details.
• signal.send_sig_queue.return — queuing a signal to a process completed
  • See probe::signal.send_sig_queue.return(3stap) for details.
• signal.pending — examining pending signal 🔍
  • See probe::signal.pending(3stap) for details.
• signal.pending.return — examination of pending signal completed
  • See probe::signal.pending.return(3stap) for details.
• signal.handle — signal handler being invoked 🫡
  • See probe::signal.handle(3stap) for details.
• signal.handle.return — signal handler invocation completed
  • See probe::signal.handle.return(3stap) for details.
• signal.do_action — examining or changing a signal action 🔧
  • See probe::signal.do_action(3stap) for details.
• signal.do_action.return — examining or changing a signal action completed
  • See probe::signal.do_action.return(3stap) for details.
• signal.procmask — examining or changing blocked signals 🚫
  • See probe::signal.procmask(3stap) for details.
• signal.procmask.return — examining or changing blocked signals completed
  • See probe::signal.procmask.return(3stap) for details.
• signal.flush — flushing all pending signals for a task 🚽✨ (sorry, it's a flushing joke, I had to)
  • See probe::signal.flush(3stap) for details.

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🎀 and now the little helper functions 🎀

these are the glow-up utilities, the ones you call when you want a signal thing turned into something readable, iykyk 💅

• get_sa_flags — returns the numeric value of sa_flags 🔢
  • See function::get_sa_flags(3stap) for details.
• get_sa_handler — returns the numeric value of sa_handler 🔢
  • See function::get_sa_handler(3stap) for details.
• sigset_mask_str — returns the string representation of a sigset 🪄
  • See function::sigset_mask_str(3stap) for details.
• is_sig_blocked — returns 1 if the signal is currently blocked, or 0 if it is not ✅❌
  • See function::is_sig_blocked(3stap) for details.
• sa_flags_str — returns the string representation of sa_flags 🪄
  • See function::sa_flags_str(3stap) for details.
• sa_handler — returns the string representation of an sa_handler 🪄
  • See function::sa_handler(3stap) for details.
• signal_str — returns the string representation of a signal number 🪄
  • See function::signal_str(3stap) for details.

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🌈 SEE ALSO 🌈

the whole friend group, go say hi 👑🫶

• function::get_sa_flags(3stap)
• function::get_sa_handler(3stap)
• function::sigset_mask_str(3stap)
• function::is_sig_blocked(3stap)
• function::sa_flags_str(3stap)
• function::sa_handler(3stap)
• function::signal_str(3stap)
• probe::signal.send(3stap)
• probe::signal.send.return(3stap)
• probe::signal.checkperm(3stap)
• probe::signal.checkperm.return(3stap)
• probe::signal.wakeup(3stap)
• probe::signal.check_ignored(3stap)
• probe::signal.check_ignored.return(3stap)
• probe::signal.force_segv(3stap)
• probe::signal.force_segv.return(3stap)
• probe::signal.syskill(3stap)
• probe::signal.syskill.return(3stap)
• probe::signal.sys_tkill(3stap)
• probe::signal.systkill.return(3stap)
• probe::signal.sys_tgkill(3stap)
• probe::signal.sys_tgkill.return(3stap)
• probe::signal.send_sig_queue(3stap)
• probe::signal.send_sig_queue.return(3stap)
• probe::signal.pending(3stap)
• probe::signal.pending.return(3stap)
• probe::signal.handle(3stap)
• probe::signal.handle.return(3stap)
• probe::signal.do_action(3stap)
• probe::signal.do_action.return(3stap)
• probe::signal.procmask(3stap)
• probe::signal.procmask.return(3stap)
• probe::signal.flush(3stap)
• stap(1)
• stapprobes(3stap)

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and that's the whole page, bestie, we ate and left no crumbs 💅 this was the SystemTap Tapset Reference version of TAPSET::SIGNAL(3stap), dated September 2026 — go forth and probe responsibly, mwah 🫶💖✨