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