---
name: "lgfile"
section: "5"
platform: "linux"
package: "ion"
version: "3.2.1+dfsg-1.1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/lgfile"
---

# lgfile(5)

ION Load/Go source file

## NAME

lgfile - ION Load/Go source file

## DESCRIPTION

The ION Load/Go system enables the execution of ION administrative programs at remote nodes:

The **lgsend** program reads a Load/Go source file from a local file system, encapsulates the text of that source file in a bundle, and sends the bundle to a designated DTN endpoint on the remote node.

An **lgagent** task running on the remote node, which has opened that DTN endpoint for bundle reception, receives the extracted payload of the bundle -- the text of the Load/Go source file -- and processes it.

Load/Go source file content is limited to newline-terminated lines of ASCII characters.  More specifically, the text of any Load/Go source file is a sequence of *line sets* of two types: *file capsules* and *directives*. Any Load/Go source file may contain any number of file capsules and any number of directives, freely intermingled in any order, but the typical structure of a Load/Go source file is simply a single file capsule followed by a single directive.

Each *file capsule* is structured as a single start-of-capsule line, followed by zero or more capsule text lines, followed by a single end-of-capsule line.  Each start-of-capsule line is of this form:

\[*file\_name*

Each capsule text line can be any line of ASCII text that does not begin with an opening (\[) or closing (\]) bracket character.

A text line that begins with a closing bracket character (\]) is interpreted as an end-of-capsule line.

A *directive* is any line of text that is not one of the lines of a file capsule and that is of this form:

!*directive\_text*

When **lgagent** identifies a file capsule, it copies all of the capsule's text lines to a new file named *file\_name* that it creates in the current working directory.  When **lgagent** identifies a directive, it executes the directive by passing *directive\_text* to the *pseudoshell()* function (see [*platform*(3)](/platform/3.md)).  **lgagent** processes the line sets of a Load/Go source file in the order in which they appear in the file, so the *directive\_text* of a directive may reference a file that was created as the result of processing a prior file capsule line set in the same source file.

Note that lgfile directives are passed to *pseudoshell()*, which on a VxWorks platform will always spawn a new task; the first argument in *directive\_text* must be a symbol that VxWorks can resolve to a function, not a shell command.  Also note that the arguments in *directive\_text* will be actual task arguments, not shell command-line arguments, so they should never be enclosed in double-quote characters (").  However, any argument that contains embedded whitespace must be enclosed in single-quote characters (') so that *pseudoshell()* can parse it correctly.

## EXAMPLES

Presenting the following lines of source file text to **lgsend**:

\[cmd33.bprc

x protocol ltp

\]

!bpadmin cmd33.bprc

should cause the receiving node to halt the operation of the LTP convergence-layer protocol.

## SEE ALSO

[*lgsend*(1)](/lgsend/1.md), [*lgagent*(1)](/lgagent/1.md), [*platform*(3)](/platform/3.md)