Jouke Witteveen

NAME

respond —

automate response actions for events that are reported by a logging system (such as syslog).

SYNOPSIS

respond -a FILE [-p FILE]

DESCRIPTION

respond listens on stdin or on the named pipe specified by -p and matches each line it reads to the regular expressions it finds in the actionscript specified by -a. If a line matches, respond executes a rewritten command specified in the actionscript.

OPTIONS

-a FILE: Specifies the actionscript (FILE) to read the actions (see below) from.
-p FILE: Specifies the location (FILE) of the named pipe. If the pipe does not exist it will be created for the running time of respond. For a discription of the creation of a named pipe see: mkfifo(1). respond locks the directory of the pipe and processes relative paths in the actionscript as relative to this directory.

ACTIONSCRIPT SNTAX

Each line in actionscript (unless commented with '#') specifies a regular expression/command pair, sepperated by whitespace. As a result of this syntax whitespace in the expression or the command needs to be commented by either preceeding it with '\' or by placing it inside a quoted ('"') string. You need to escape '"' and '\', even when they are within quotes. In addition to this the '$'-character has special behaviour inside the command. When not escaped $n will translate to the matched subexpression n (if existing) and $0 will be replaced by the entire match. Information on subexpressions as well as on the syntax used for the regular expressions is provided in a seperate manual (re_format(7) for the default regex library).

DIAGNOSTICS

Although respond will detach from the terminal that calls it, it is as much a daemon as it has the "~d" suffix. This means that it does, for one thing, not drop privileges. This is really a feature and not a bug since it makes it possible to control multiple actionscripts for multiple users without the need of a configuration file.

TROUBLESHOOTING

The most likely reason for respond to not start is a malformed actionscript. When a read error is reported be sure to triple check the syntax used in your actionscript. In some cases too long lines in the actionscript can also trigger a read error.

A sudden dead of respond will probably be caused by a failure reading the named pipe. Normally though, respond quits when it receives a SIGINT or SIGTERM signall from kill(1).