"Built-In" Functions in REXX:

• A major strength of the REXX language is it's standard "built-in" functions
• A complete implementation of the standard provides between sixty-four and sixty-seven functions (depends on the I/O model adopted);
• Individual implementations may include additional functions, if needed
• The "built-in" REXX functions provide these services:
  • I/O and File-Related Services:
    These functions tend to be specific to the implementation for a particular operating system.
    • The official I/O model uses the charin/charout/linein/lineout functions
    • The "unofficial" I/O model, developed by IBM for its operating system (which do not support character or line input and output) uses the execio function
  • System Services:
    These functions return information about the state of some element of the system or preserve/restore information about state.

  • Data Conversion and Numeric Services:
    REXX has a single datatype -- the string. It has, however, a powerful set of conversion and numeric functions used to transform the numeric presentation of data.

  • String Manipulation Services:
    Most of the built-in functions support a variety of string manipulation services.

  • Error Handling Services:
    REXX error-handling functions provide means for "gracefully" managing errors that may occur during execution.

Next