ref: 70f700699ac06fb33267395c60f62b4fae3f4f15
dir: /sys/man/4/ptrap/
.TH PTRAP 4 .SH NAME ptrap \- \fIplumber\fR(4) filter .SH SYNOPSIS .B ptrap .I port [\fB!\fR]\fIregexp\fR [ .I port [\fB!\fR]\fIregexp\fR ... ] .SH DESCRIPTION .I Ptrap is a program that mounts itself over a .IR plumber (4) service mounted at .B /mnt/plumb and filters incoming messages according to the rules provided on the command line. .PP .I Ptrap accepts an arbitrary number of argument pairs; each pair consists of a port name .I port and a regular expression .I regexp (see .IR regexp (6)). Each incoming message that does not match .I regexp is discarded. The .I regexp can be optionally prefixed by .B ! to indicate logical inversion (i.e. messages matching the regexp are discarded). .SH EXAMPLES Start a .IR sam (1) instance dedicated to editing kernel source code: .IP .EX ptrap edit '^/sys/src/9/' sam .EE .PP In another window, start a second .IR sam (1) instance for all other editing jobs: .IP .EX ptrap edit '!^/sys/src/9/' sam .EE .SH SOURCE .B /sys/src/cmd/ptrap.c .SH SEE ALSO .IR plumber (4), .IR plumb (6) .SH BUGS Multiple filters specified on the same port ignore all but the last one. .PP .I Ptrap would be more useful if it could inhibit sending the message to other clients. .PP As far as .IR plumber (4) is concerned, even messages dropped by .I ptrap are "accepted", which means rules that are supposed to apply to messages not accepted by clients are not invoked (e.g. a rule starting an editor if no one is listening to the .I edit port will not work if there is a .I ptrap on that port). .SH HISTORY .I Ptrap first appeared in 9front (February, 2018).