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System Functions Categorised

The following tables list the system functions divided into appropriate categories.

Settings Affecting Behaviour of Primitive Functions

Name Description
⎕CT Comparison Tolerance
⎕DCT Decimal Comp Tolerance
⎕DIV Division Method
⎕FR Floating-Point Representation
⎕IO Index Origin
⎕ML Migration Level
⎕PP Print Precision
⎕RL Random Link

The following table describes the dependencies that exist between functions, operators and these system variables.

Table 1: Implicit Arguments
System Variable Monadic Functions Dyadic Functions Operators
⎕CT, ⎕DCT ⌈ ⌊ ∪ ~ < ≤ = ≥ > ≠ ≡ ≢ ⍳ ∊ ∪ ∩ ⍷ | ∨ ∧
⎕DIV ÷ ÷  
⎕FR   ⍝ 1 ÷ * ⍟ ! ○ ⌹ + - × ÷ * ⍟ | ! ○ ∨ ∧ ⊥ ⊤ ⌹  
⎕FR   ⍝ 2 ⌈ ⌊ ∪ ~ < ≤ = ≥ > ≠ ≡ ≢ ⍳ ∊ ∪ ∩ ⍷
⎕FR   ⍝ 3 ⍒ ⍋ ⌈ ⌊ ⍒ ⍋ ⍸  
⎕IO ⍳ ? ⍒ ⍋ ⍸ ⍳ ? ⍒ ⍋ ⍉ ⊃ ⌷ ⍸ ⌸ @ []
⎕ML ∊ ↑ ⊃ ≡    
⎕PP    
⎕RL ? ?  

where, for ⎕FR, 1 indicates functions that compute real numbers and whose precision depends on ⎕FR, 2 indicates functions that perform tolerant comparisons and 3 indicates functions that perform tolerant comparisons.

NOTE: Tolerant comparisons depend on ⎕FR to select which of ⎕CT and ⎕DCT is used; ⎕FR also determines the precision of the comparison computation that can affect results. However, even primitives involving intolerant comparison (including the tolerant ones with all comparison tolerances set to 0) can depend on ⎕FR if the argument contains DECFs. This is because DECFs must be converted to doubles for comparison. If two DECFs are different but correspond to the same double, then they will be treated as intolerantly unequal when ⎕FR is 1287 but equal when it is 645.

Session Information/Management

Name Description
⎕AI Account Information
⎕AN Account Name
⎕CLEAR Clear workspace (WS)
⎕CY Copy objects into active WS
⎕DL Delay execution
⎕LOAD Load a saved WS
⎕OFF End the session
⎕PATH Search Path
⎕SAVE Save the active WS
⎕TS Timestamp

Constants

Name Description
⎕A Alphabetic upper case characters
⎕D Digits
⎕NULL Null Item

Tools and Access to External Utilities

Name Description
⎕C Case Convert
⎕CMD Execute the Windows Command Processor or another program
⎕CMD Start a Windows AP
⎕CSV Comma Separated Values
⎕DR Data Representation (Monadic)
⎕DR Data Representation (Dyadic)
⎕DT Datetime
⎕FMT Resolve display
⎕FMT Format array
⎕JSON JSON Convert
⎕MAP Map a file
⎕NA Declare a DLL function
⎕R Replace
⎕S Search
⎕SH Execute a UNIX command or another program
⎕SH Start a UNIX AP
⎕UCS Unicode Convert
⎕USING Microsoft .NET Search Path
⎕VFI Verify and Fix numeric
⎕XML XML Convert

Manipulating Functions and Operators

Name Description
⎕AT Object Attributes
⎕CR Canonical Representation
⎕ED Edit one or more objects
⎕EX Expunge objects
⎕FX Fix definition
⎕LOCK Lock a function
⎕MONITOR Monitor set
⎕MONITOR Monitor query
⎕OR Object Representation
⎕NR Nested Representation
⎕PROFILE Profile Application
⎕REFS Local References
⎕STOP Set Stop vector
⎕STOP Query Stop vector
⎕TRACE Set Trace vector
⎕TRACE Query Trace vector
⎕VR Vector Representation

Namespaces and Objects

Name Description
⎕BASE Base Class
⎕CLASS Class
⎕CS Change Space
⎕DF Display Format
⎕FIX Fix
⎕INSTANCES Instances
⎕NEW New Instance
⎕NS Namespace
⎕SRC Source
⎕THIS This

Input and Output

Name Description
Evaluated Input/Output
Character Input/Output
⎕ARBIN Arbitrary Input
⎕ARBOUT Arbitrary Output
⎕RTL Response Time Limit

Component Files

Name Description
⎕FAPPEND Append a component to File
⎕FAVAIL File system Availability
⎕FCHK File Check and Repair
⎕FCOPY Copy a File
⎕FCREATE Create a File
⎕FDROP Drop a block of components
⎕FERASE Erase a File
⎕FHIST File History
⎕FHOLD File Hold
⎕FLIB List File Library
⎕FNAMES Names of tied Files
⎕FNUMS Tie Numbers of tied Files
⎕FPROPS File Properties
⎕FRDAC Read File Access matrix
⎕FRDCI Read Component Information
⎕FREAD Read a component from File
⎕FRENAME Rename a File
⎕FREPLACE Replace a component on File
⎕FRESIZE File Resize
⎕FSIZE File Size
⎕FSTAC Set File Access matrix
⎕FSTIE Share-Tie a File
⎕FTIE Tie a File exclusively
⎕FUNTIE Untie Files

Native Files

Name Description
⎕MKDIR Create a directory
⎕NAPPEND Append to File
⎕NCOPY Copy files and directories
⎕NCREATE Create a File
⎕NDELETE Delete a File or Directory
⎕NERASE Erase a File
⎕NEXISTS Discover whether or not a file or directory exists
⎕NGET Read Text File
⎕NINFO Obtain information about one or more files and/or directories
⎕NLOCK Lock a region of a file
⎕NMOVE Move files and directories
⎕NNAMES Names of tied Files
⎕NNUMS Tie Numbers of tied Files
⎕NPARTS Split a file name into its constituent parts.
⎕NPUT Write Text File
⎕NREAD Read from File
⎕NRENAME Rename a File
⎕NREPLACE Replace data on File
⎕NRESIZE File Resize
⎕NSIZE File Size
⎕NTIE Tie a File exclusively
⎕NUNTIE Untie Files
⎕NXLATE Specify Translation Table

Threads

Name Description
⎕TALLOC Allocate Token Range
⎕TCNUMS Thread Child Numbers
⎕TID Current Thread Identity
⎕TKILL Kill Threads
⎕TNAME Current Thread Name
⎕TNUMS Thread Numbers
⎕TSYNC Wait for Threads to Terminate

Synchronisation

Name Description
⎕TALLOC Allocate Token Range
⎕TGET Get Tokens
⎕TKILL Kill Threads
⎕TPOOL Token Pool
⎕TPUT Put Tokens
⎕TREQ Token Requests

Error Handling

Name Description
⎕DM Diagnostic Message
⎕DMX Extended Diagnostic Message
⎕EM Event Messages
⎕EN Event Number
⎕EXCEPTION Reports the most recent Microsoft .NET Exception
⎕SIGNAL Signal event
⎕TRAP Event Trap

Stack and Workspace Information

Name Description
⎕LC Line Count
⎕LX Latent Expression
⎕NC Name Classification
⎕NL Name List
⎕NSI Namespace Indicator
⎕RSI Space Indicator
⎕SI State Indicator
⎕SHADOW Shadow names
⎕SIZE Size of objects
⎕STACK Report Stack
⎕STATE Return State of an object
⎕WA Workspace Available
⎕WSID Workspace Identification
⎕XSI Extended State Indicator

Shared Variables

Name Description
⎕SVC Set access Control
⎕SVC Query access Control
⎕SVO Shared Variable Offer
⎕SVO Query degree of coupling
⎕SVQ Shared Variable Query
⎕SVR Retract offer
⎕SVS Query Shared Variable State

GUI and COM Support

Name Description
⎕DQ Await and process events
⎕EXPORT Export objects
⎕NQ Place an event on the Queue
⎕WC Create GUI object
⎕WG Get GUI object properties
⎕WN Query GUI object Names
⎕WS Set GUI object properties
⎕WX Expose GUI property names

Miscellaneous

Name Description
⎕Ⓐ Underscored Alphabetic Characters
⎕AV Atomic Vector
⎕AVU Atomic Vector - Unicode
⎕KL Key Labels
⎕PFKEY Programmable Function Keys
⎕SD Screen Dimensions
⎕SM Screen Map
⎕SR Screen Read
⎕OPT Variant Operator
⎕TC Terminal Control
⎕XT Associate External variable
⎕XT Query External variable