Via mql(1) as a command

Overview

You can use the mql(1) program for interfacing with Emdros. In C, this is typically done with the system() library-call. Scripting-languages such as Ruby, Perl, and Python have their own ways of calling external programs.

Benefits

Benefits include:

• Simplicity: The only APIs to learn are:

  • The MQL language itself (which you must learn anyway),

  • The format of the MQL output,

  • The exit-status codes of the mql(1) program.

Drawbacks

Drawbacks include:

• Less performance:

  • Output must be parsed and the datastructures recreated. This takes both space and time.

  • mql(1) process must be started and stopped for each collection of MQL statements you wish to have evaluated. This takes time.

  • Back-end connection is established and broken together with the mql(1) process. This takes time.

• Less flexibility: You can only interface with Emdros via the MQL language, not the EMdF API.

That having been said, it may be possible to keep the mql(1) process running, keeping an open pipe between your application and the mql(1) process. If so, the only performance-problem that remains is the parsing of the output.