1.fp 5 CW
2.de Af
3.ds ;G \\*(;G\\f\\$1\\$3\\f\\$2
4.if !\\$4 .Af \\$2 \\$1 "\\$4" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9"
5..
6.de aF
7.ie \\$3 .ft \\$1
8.el \{\
9.ds ;G \&
10.nr ;G \\n(.f
11.Af "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9"
12\\*(;G
13.ft \\n(;G \}
14..
15.de L
16.aF 5 \\n(.f "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"
17..
18.de LR
19.aF 5 1 "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"
20..
21.de RL
22.aF 1 5 "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"
23..
24.de EX		\" start example
25.ta 1i 2i 3i 4i 5i 6i
26.PP
27.RS 
28.PD 0
29.ft 5
30.nf
31..
32.de EE		\" end example
33.fi
34.ft
35.PD
36.RE
37.PP
38..
39.TH SIG 3
40.SH NAME
41sig \- signal interface routines
42.SH SYNOPSIS
43.L "#include <ast.h>"
44.L "#include <sig.h>"
45.sp
46.L "int sigunblock(int sig);"
47.L "int sigcritical(int op);"
48.SH DESCRIPTION
49.L sigunblock
50is called to
51unblocks the signal
52.L sig
53from within a handler currently servicing
54.LR sig .
55.PP
56.L sigcritical
57controls a critical region for the
58.LR SIGINT ,
59.L SIGQUIT
60and
61.L SIGHUP
62signals.
63.L "op > 0"
64pushes the region,
65.L "op == 0"
66pops the region, and
67.L "op < 0"
68returns non-zero if any signals are being held in the current
69critical region.
70Signal critical regions may be nested.
71The current critical region level is returned,
72.L \-1
73on error.
74.SH "SEE ALSO"
75signal(2)
76