.TH megaco_flex_scanner 3erl "megaco 3.19.5" "Ericsson AB" "Erlang Module Definition"
.SH NAME
megaco_flex_scanner \- Interface module to the flex scanner linked in driver.
.SH DESCRIPTION
.LP
This module contains the public interface to the flex scanner linked in driver\&. The flex scanner performs the scanning phase of text message decoding\&.
.LP
The flex scanner is written using a tool called \fIflex\fR\&\&. In order to be able to compile the flex scanner driver, this tool has to be available\&.
.LP
By default the flex scanner reports line-number of an error\&. But it can be built without line-number reporting\&. Instead token number is used\&. This will speed up the scanning some 5-10%\&. Use \fI--disable-megaco-flex-scanner-lineno\fR\& when configuring the application\&.
.LP
The scanner will, by default, be built as a reentrant scanner \fIif\fR\& the flex utility supports this (it depends on the version of flex)\&. It is possible to explicitly disable this even when flex support this\&. Use \fI--disable-megaco-reentrant-flex-scanner\fR\& when configuring the application\&.
.SH "DATA TYPES"

.LP
.nf


megaco_ports() = term()
megaco_version() = integer() >= 1
 
    
.fi
.SH EXPORTS
.LP
.B
start() -> {ok, PortOrPorts} | {error, Reason}
.br
.RS
.LP
Types:

.RS 3
PortOrPorts = megaco_ports()
.br
Reason = term()
.br
.RE
.RE
.RS
.LP
This function is used to start the flex scanner\&. It locates the library and loads the linked in driver\&.
.LP
On a single core system or if it\&'s a non-reentrant scanner, a single port is created\&. On a multi-core system with a reentrant scanner, several ports will be created (one for each scheduler)\&.
.LP
Note that the process that calls this function \fImust\fR\& be permanent\&. If it dies, the port(s) will exit and the driver unload\&.
.RE

.LP
.B
stop(PortOrPorts) -> stopped
.br
.RS
.LP
Types:

.RS 3
PortOrPorts = megaco_ports()
.br
.RE
.RE
.RS
.LP
This function is used to stop the flex scanner\&. It also unloads the driver\&.
.RE

.LP
.B
is_reentrant_enabled() -> Boolean
.br
.RS
.LP
Types:

.RS 3
Boolean = boolean()
.br
.RE
.RE
.RS
.LP
Is the flex scanner reentrant or not\&.
.RE

.LP
.B
is_scanner_port(Port, PortOrPorts) -> Boolean
.br
.RS
.LP
Types:

.RS 3
Port = port()
.br
PortOrPorts = megaco_ports()
.br
Boolean = boolean()
.br
.RE
.RE
.RS
.LP
Checks if a port is a flex scanner port or not (useful when if a port exits)\&.
.RE

.LP
.B
scan(Binary, PortOrPorts) -> {ok, Tokens, Version, LatestLine} | {error, Reason, LatestLine} 
.br
.RS
.LP
Types:

.RS 3
Binary = binary()
.br
PortOrPorts = megaco_ports()
.br
Tokens = list()
.br
Version = megaco_version()
.br
LatestLine = integer()
.br
Reason = term()
.br
.RE
.RE
.RS
.LP
Scans a megaco message and generates a token list to be passed on the parser\&.
.RE