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7.17.1 Process Library Specifics

The process library objects provide collections of interfaces (functions and data types) concerned with process execution.

Central to the provided interfaces are the shell data types - objects describing process execution contexts. They record both the execution method (in such details as path, command line, etc) and the execution state and its results.

Two data types are made available by the process library objects: ‘sshell’ and ‘xshell’.

The ‘sshell’ data type describes execute-and-wait process execution contexts. The ‘sshell’ objects record the executed process output.

The ‘xshell’ data type describes pipe-and-start process execution contexts.

The shell objects aggregate objects of such types as list, time, file and byta data. The operation of the shell objects is largely available via the aggregated objects. The aggregated objects are regular constructs of data types provided by the list, time, file and byta data library objects.

See List Library.

See File Library.

See Date And Time Library.

See Byte Data Library.

The various properties of the process execution contexts are described via the aggregated objects. Thus, the shell objects describe the list of command line arguments of the executed processes as a ‘list’ object and the path to the executable as a ‘data’ object.

The aggregated objects are full fledged objects of their respective types. They may be interogated from the shell objects and do retain a identity beyond that of their shell aggregators. They may even survive the shell objects (if they are linked into other aggregators (such as ‘list’ containers) or associated with variables).