SIG(3ast) SIG(3ast)

# [NAME](#NAME)

sig - signal interface routines

# [SYNOPSIS](#SYNOPSIS)

```
#include <ast.h>
#include <sig.h>

int sigunblock(int sig);
int sigcritical(int op);
```

# [DESCRIPTION](#DESCRIPTION)

**sigunblock** is called to unblock the signal **sig** from within a handler currently servicing **sig**.

**sigcritical** controls a critical region for the **SIGINT**, **SIGQUIT** and **SIGHUP** signals. **op &gt; 0** pushes the region, **op == 0** pops the region, and **op &lt; 0** returns non-zero if any signals are being held in the current critical region. Signal critical regions may be nested. The current critical region level is returned, **-1** on error.

# [SEE ALSO](#SEE_ALSO)

[signal(2)](/man/os/ksh/signal.2)

---

Document: sig(3ast) from ksh 1.0.10-r36 (Chainguard OS)
Source: https://github.com/ksh93/ksh