Help > Authoring > Working with Links > Link and Target Processing Instructions
  
Link and Target Processing Instructions
You can insert _link and _target processing instructions (PIs) using Tools > Create Hyperlink. (The optional hyperlink menu items can be enabled with the set hyperlinkmenus command.)
When you use Tools > Create Hyperlink to insert links, the region the user clicks on is enclosed by _link PIs. The destination linked to is marked with a UDT of the _target PI. The _link and _target PIs are hidden in the Edit Window unless you select Tools > Show Hyperlinks.
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This PI has no effect on published output, except when the Print attribute is set to no. Then the contents of _link are suppressed.
Using ACL, you can set several other attributes in addition to those available in the Modify Attributes dialog box:
MenuLabel — Controls what appears in the Link menu item on the M3 menu. This attribute does not display in Arbortext Editor even if the _link PI does.
Func — Names an ACL function that performs the linking action. If set, this attribute takes precedence over all other link-governing attributes (that is, the other link-governing attributes are ignored).
attr1, attr2, and attr3 — Specify generic attributes that applications developers can define.