Understanding the AE runtime system

The AE API can be used in processes that are not started by the AE runtime system. However, it is usually more convenient to allow the AE runtime system to control the lifespan of an AE application, or to use it to launch an AE application that then controls its own lifespan.

AE runtime options can be set and specified by using AE and/or environment variables, which are key/value pairs similar to UNIX environment variables. The command line utility to register AEs, register_ae, can be used to set these variables implicitly by using command line options. Using the register_ae --environment option, AE environment variables can also be set directly, overriding variables set by register_ae.

Using the AE runtime system to launch an AE provides considerable control over the process start upstate. Items that can be specified include the executable file path, command line arguments to the executable, the value of system environment variables such as PATH and LD_LIBRARY_PATH, and application-specific operating system environment variables. Different environment variable value scan is specified on the host instead of the SPU, including the logging level.

The process that started by the AE runtime does not have to be the process that uses the AE API to perform data processing. For example, the AE runtime might be used to run a script that then executes a program that uses the AE API.