Batch mode
Batch mode is the EDT operating mode in which no terminal is present. EDT can then only operate in L mode.
Character set
EDT V17.0A makes it possible to process texts in all the character sets made available by XHCS. In addition to the character sets supported in EDT V16.6B and compatibility mode, the character sets supported in Unicode mode include the three Unicode character sets, ISO character sets and, if necessary, the 7-bit character sets.
In each work file it is possible to configure a different character set so that texts in different character sets can be processed in parallel. A communications character set is configured to permit communication with a terminal.
Communications character set
Character set used by EDT in Unicode mode to communicate with the terminal. This can be different from the character set used by the current or any other work file. The communications character set is usually optimally suited to the capabilities offered by the terminal.
Compatibility mode
Compatibility mode is an EDT V17.0A operating mode. Compatibility mode provides the full functionality of EDT V16.6B. However, the extended functions of EDT V17.0A cannot be used. For example, it is not possible to process Unicode files and the record length continues to be restricted to 256 bytes.Under some circumstances, there may be an implicit switchover to Unicode mode if a Unicode file is read or an explicit switchover may occur if a @MODE statement is entered.
Data window
Field in the data window in which the current work file is displayed. The work file records are output in the data window's screen lines.
Delimiter characters
Literals are usually enclosed by the delimiter character apostrophe (or single quote, default value '). When a search is performed using the @ON statement, it is possible to use a special delimiter character, namely the quotation mark (default value "). This specifies that a string is only recognized as a hit if it is delimited by text delimiters. The text delimiter characters consist of a
configurable set of characters which, by default, include the space character, parentheses etc.
@DO procedure
A @DO procedure is an EDT procedure which is stored in a work file. It can be run by means of a @DO statement. @DO procedures provide a number of statements used for runtime control. At call time, it is possible to pass
parameters to these statements which can also be nested.
EDT procedures
An EDT procedure is a sequence of entries, statements and/or records sent to EDT and stored in a file (@INPUT procedure) or work file (@DO procedure).
EDT start procedure
The EDT start procedure is a special @INPUT procedure which (if present) is run when EDT is started.
EDT statement symbol
The EDT statement symbol is a special character used to identify statements. By default, this is the character @ which is therefore consistently used in this document.
EDT variables
EDT variables are containers which can be used to store values across work file boundaries. EDT variables are only valid for the current EDT session.
There are three types of variables which can be assigned the corresponding values. 21 variables of each variable type are available.
Integer variables (
#I0..#I20)String variables (
#S0..#S20)Line number variables (
#L0..#L20)
Full screen mode (F mode)
Full screen mode (F mode) is an EDT work mode. In F mode, the entire screen is available as a work window for the entry of data and statements. It is possible to switch from F mode to L mode. EDT can only operate in interactive mode in F mode.
@INPUT procedure
An @INPUT procedure is an EDT procedure which is stored in a file or library element. It can be run by means of an @INPUT statement. The runtime control statements are not (directly) available in @INPUT procedures. These
statements cannot be nested and it is not possible to pass any parameters. It is, however, possible to call @DO statements.
Interactive mode
Interactive mode is the EDT operating mode in which a terminal is present. This is the only mode in which EDT can operate in F mode.
Line mode (L mode)
Line mode (L mode) is an EDT work mode. In L mode, files are processed lineby-line, that is to say that in dialog operation EDT only outputs one line (the current line) at a time or only reads one line (in both batch and dialog operation) from SYSDTA. This line may contain records or statements and is processed as soon as it has been read in.
Line number
A line number is assigned to every record in a work file. This line number uniquely identifies the record. A line number is the current line number in which data is entered in L mode.
Operating mode
Since it was not possible to implement the extensions required for Unicode support in a way which would ensure compatibility, a new EDT operating mode has been introduced. EDT V17.0A can therefore be used in two modes: Unicode mode and compatibility mode.
In Unicode mode, a range of extensions are available. Most importantly, it is possible to process Unicode files (only) in Unicode mode.
However, this mode is not compatible with EDT V16.6B in all respects.
In contrast, compatibility mode provides the full functionality of EDT V16.6B. However, the extensions are not available in this mode.
By default, EDT V17.0A is started in compatibility mode. A new statement is available to start it in Unicode mode.
Operating types
A distinction is made between two types of operation depending on whether or not a terminal is present. In interactive mode, a terminal is present whereas it is not in batch mode.
Record mark
Every record in a work file can be flagged with a record mark which is invisible to users. These marks can be set, queried and deleted using statements and statement codes. Once marked, records can, for example, be copied or deleted.
Screen dialog
The statement @DIALOG – which can only be entered at the subroutine interface or by SYSDTA – is used to switch EDT to screen dialog. In screen dialog, the preceding read operation is interrupted and EDT reads its input from the terminal in F mode (or in L mode after the entry of @EDIT). The screen dialog can be exited again with @HALT, @END, @RETURN or [K1]. EDT then continues the interrupted read operation.
Screen line
Lines in the data window in which the records of the current work file are output.
Statement
Inputs to EDT take the form either of records or statements. Statements are used either to activate EDT functions or make parameter settings. In order to distinguish between statements and records, statements must be entered in line mode with the EDT statement symbol. In F mode, statements are entered in the statement line There are also statement codes which are entered in the statement code column.
Statement buffer
EDT saves the most recent statements entered in F mode in a buffer. These statements can then be retrieved from this buffer.
Statement code
Statement codes are 1 character long statements which can be entered in the statement code column in F mode.
Statement code column
The statement code column is a field in the work window in which statement codes can be entered.
Statement line
A work window field in F mode. Entries in the statement line are interpreted as statements. The EDT statement symbol can normally be omitted.
Substitute character
When strings are converted from one character set to another, it is possible that characters in the source character set may not be present in the target
character set. In such cases, the substitute character is used (if it has been defined). If no substitute character has been defined then conversion is usually rejected.
Unicode mode
Unicode mode is an EDT operating mode. The extended EDT V17.0A functions are only available in Unicode mode, i.e. only in this Unicode mode is it possible to process Unicode files, can records exceed 256 bytes in length, are local character sets available etc.
However, this mode is not compatible with EDT V16.6B in all respects. In particular, there are incompatibilities in terms of the subroutine interface. In addition, a large number of inconsistencies have been eliminated.
Unicode substitute representation
In both statements in literals and in data, EDT permits the substitute
representation of Unicode characters through the specification of the
associated UTF16 code. This makes it possible to enter all the (supported) characters via an escape character even if the character set for the statement or the data is not a Unicode character set.
User statement symbol
A user statement symbol is a special character which identifies user statements which are executed using external statement routines.
Wildcards
Wildcards are placeholders for groups of characters in a search string. Here, the asterisk (default value *) stands for a string of any length (including an empty
string) and the slash (default value /) for precisely one character.
Work file
In EDT, data is always entered and processed in a work file. In work files, it is
possible, for example, to insert, edit and delete data. The content of work files
can be displayed on screen. If it is necessary to process the content of a file
(DMS file, library element or POSIX file) then this content must first be
transferred to a work file. After processing, the content of a work file can be
written back to a file.
EDT is able to manage 23 work files. The work files are organized into records
to which line numbers are assigned.
Work file, active
An active work file is a work file which contains a @DO procedure which is currently being executed. If there are nested @DO procedures then multiple work files may be active.
Work file, current
A single work file is the current work file. Data is entered in this work file and statements are effective within it. In F mode, a section of the current work file is displayed on the screen.
Work file, empty
An empty work file is a work file which contains no records. However, an empty work file may also contain properties which do not correspond to the initial state, for example it can be considered to be occupied or linked to a file. A work file is only reset to its original state following a @DELETE statement (format 2) or other statements which completely delete work files either implicitly or explicitly.
Work mode
EDT provides two work modes for data processing: line mode (L mode) and full screen mode (F mode).
In L mode, only one screen line is available for the entry of data and statements at any time.
In F mode, the entire screen is available for the entry of data and statements.The work modes should not be confused with the EDT operating modes (compatibility mode and Unicode mode). While the work modes relate to differences in the way data is displayed and processed, the operating modes represent different EDT environments with a restricted or extended function scope.
Work window
In F mode, the current work file is displayed on the screen. In this case, the screen is subdivided into fields with different functions. Alongside the data window in which the content of the current work file is displayed, the work window contains a statement line and a statement code column together with other elements.