COBOL Source Information | Editor |
The File Specification and Directory Facility (referred to in this manual simply as the Directory Facility) enables you to select files for processing within Object COBOL.
There are many places in the Object COBOL Development Environment where you are required to enter a filename. At each of these places, a similar file specification menu is displayed which includes the option to display a directory listing and select a file from within it by simply pointing with the cursor. The features which are common to all such menus are described in this chapter.
This section describes the menus of the Directory Facility and its two main functions: how to enter a filename efficiently, and how to obtain and tailor a directory listing.
UNIX :
Throughout this chapter, references to pressing keys such as function
or status keys imply the logical pressing and releasing of these keys
rather than the physical keystrokes. Some keys are symbolic key names
which may not be present on your keyboard. See the appendix UNIX Key
Usage Chart for details on the actual keystrokes required to achieve
the documented function.
Whenever you have to load or save a file when you are using an Object COBOL component, you will do so by accessing the Directory Facility. The function you use to enter the Directory Facility may vary, but once you have entered it, a common menu, the File Specification menu, is displayed. The menu may have additional variable functions depending on which component you have invoked it from.
The general appearance of the File Specification menu is as shown in Figure 6-1.
Figure 6-1: File Specification Menu
If you have been working with a particular file during a session, its name will appear as the default at the File prompt; otherwise, the current drive and/or path are displayed.
The bottom line of the screen is used for temporary messages, which clear either when a key is pressed or after a short time has elapsed.
There are three common functions on the main menu: Help, Directory and Escape. Other functions shown on this menu depend upon the component you are using and are not described here; they will be described with that component. The Help function will also describe those options, and will again depend upon which component you are using.
In addition, there is a Control menu of functions, which is displayed when you press the Ctrl key. This menu is shown in Figure 6-2.
The Control menu also displays the File prompt; you can select and change the current default directory from this menu as well as from the main menu.
You can change the displayed drive (for DOS, Windows or OS/2 systems), path and filename by typing over the displayed name. On initial display of this prompt, the cursor will be positioned at the start of the filename area within the file specification.
In addition to the keys that you would normally expect to use when typing in a filename, some special key actions are defined to reduce the number of keystrokes you have to make.
UNIX:
Because UNIX terminals vary widely, the keys documented in this
chapter may not be available on your keyboard. See the appendix UNIX
Key Usage Chart for details on the actual keystrokes required to
achieve the documented functionality.
In all environments, the following keys are defined:
Key |
Function |
---|---|
. (period) | If entered in over-strike mode (Insert is off) all characters up to the next ".", "\" (for DOS, Windows and OS/2) or "/" (for UNIX systems) characters are erased. |
Space | Erases all characters up to the next ".", "\" (for DOS, Windows and OS/2) or "/" (for UNIX systems) characters. |
DOS, Windows and OS/2:
On DOS, Windows and OS/2 the following keys are also defined:
UNIX:
On UNIX the following key is also defined:
You can also use the following cursor keys to move through the constituent fields of the file specification:
Key |
Function |
---|---|
Tab | Moves the cursor right one field. |
Backtab | Moves the cursor left one field. |
<right-arrow> | Moves the cursor right one character position. |
<left-arrow> | Moves the cursor left one character position. |
Home | Moves the cursor to the start of the current field then to the start of the file specification. |
End | Moves the cursor to the end of the current field then to the end of the file specification. |
Ctrl+Home | Erases all characters preceding the current cursor position. |
Ctrl+End | Erases all characters from the current cursor position
onward.
|
You can specify the filename of a file which is a constituent member of a library file supplied with this COBOL system. Simply include the name of the library file as though it were the last part of the path-name.
Example
DOS, Windows and OS/2:
For example, to access myfile.cbl from within c:\path\mylib.lbr
on DOS, Windows and OS/2, you could specify:
c:\path\mylib.lbr\myfile.cbl
UNIX:
To access myfile.cbl from within /path/mydir/mylib.lbr
on UNIX, you could specify:
path/mydir/mylib.lbr/myfile.cbl
Once you have keyed in your File specification, the two main functions you can perform are the Enter function and the Directory function, described in the following sections.
If the file specification at the File prompt contains wild-cards, or it has an extension with no associated name, Enter invokes the Directory function (described below); otherwise, it executes the function that caused display of the file prompt (for example, load-file or save-file).
This function lists files for the drive (DOS, Windows and OS/2 only) and path specified by the File prompt. If a file extension is specified, all files with that extension are listed; otherwise, extensions appropriate to the current function are listed.
For example, for the Edit Load-file menu the defaults are .cbl, .CBL, .cpy, .CPY, .cob, .COB, and files with no extension. You can also include the wild-card characters "?" and "*", in which case filename as well as extension is used as one of the directory search criteria. If a filename is selected from the directory (by using the Enter function), that filename replaces the one currently displayed at the File prompt.
If you just specify a path-name with no filename following, you should include a terminating backslash (\) in the Professional COBOL Environment or a terminating slash (/) in the Object COBOL Development Environment.
You can include a library name in your path-name if you want to list the members of a library.
Example
DOS, Windows and OS/2:
For example, if you want to see the members of the library mylib.lbr,
on DOS, Windows and OS/2 you could specify:
c:\path\mylib.lbr\*
UNIX:
On UNIX, you would specify:
/path/mylib.lbr/*
The directory function lists files for the drive and/or path specified in the file prompt as described above.
Once you select the Directory function, you have access to another series of functions that enable you to change the display order of files within a directory, change and list directories, delete files and, for DOS, Windows and OS/2 systems, change the current disk drive designation. These functions are presented on the List Files menu (which incorporates a Control menu).
Once you are in this menu, F3=list-dirs gives you access to a similar menu called the List Directories menu, which provides additional functions for manipulating directories.
The top line of the menu identifies the drive and/or path of the directory listed. The four lines shown in Figure 6-3 appear at the bottom of your screen.
The first line is the information line. It displays the current default drive and/or path, the current setting of certain menu options, and the Ins, Caps, Num, and Scroll indicators.
Note: Num Lock is not recognized by UNIX.
To select a file from the displayed directory, position the cursor on the desired filename using the cursor keys (described below). If the cursor is positioned on a Micro Focus library name, the F2 option changes to F2=list-lbr-catalog. Press Enter. This returns you to the File Specification menu and enters the specified filename at the filename prompt.
DOS, Windows and OS/2:
The last line on the screen (the message line) displays statistics
(in bytes) relating to total capacity, available space and space used by
the files.
Some of the functions are presented on a Control menu - to see this menu, press the Ctrl key (see Figure 6-4).
Figure 6-4: List Files Control Menu
In addition to the cursor movement keys available as menu options, you can use the following keyboard keys and combinations to move through the directory listing.
UNIX:
Because UNIX terminals vary widely, the keys documented in this
chapter may not be available on your keyboard. See the appendix UNIX
Key Usage Chart for details on the actual keystrokes required to
achieve the documented functionality.
Key |
Function |
---|---|
Page-Up | Moves the cursor to the top of the previous screen of the listing. |
Page-Down | Moves the cursor to the top of the next screen of the listing. |
Home | Moves the cursor to the first file/directory listed on the current screen. |
End | Moves the cursor to the last file/directory listed on the current screen. |
Ctrl+Home | Moves the cursor to the first file/directory listed. |
Ctrl+End | Moves the cursor to the last file/directory listed. |
<up-arrow> | Moves the cursor up one line. |
<down-arrow> | Moves the cursor down one line. |
This section describes all the functions available on the menus. The functions in this facility fall naturally into two groups:
File Specification functions are available from the Main menu (or the File Specification menu) and its Control menu. Directory functions are available (after you have entered the Directory function) from the List Files (or List Directories) menu.
These functions are available from the File Specification menu.
brs displays the contents of a file. You must have a complete filename specified at the File prompt for this function to operate. You can scroll down the file but not up. The Browse menu lets you use four keys:
Key |
Function |
---|---|
<down-arrow> | Scrolls the text up one line (moves the view down one line). |
Enter | Same as <down-arrow>. |
Page-Down | Scrolls the text up one page minus one line (moves the view down one page minus one line). |
Escape | Returns to the invoking menu. |
call-lbr loads the library catalogue specified by the library name currently displayed at the file prompt.
Note: This function is not available under UNIX.
cancl-lbr unloads the library catalogue specified by the library name currently displayed at the file prompt.
Note: This function is not available under UNIX.
This function displays the current default directory and drive on the bottom line of the screen.
This function replaces the displayed drive and path by the current default.
This function changes the current default directory and drive to the path-name specified at the file prompt. If concurrency is in use, a warning is issued and a confirmation (Y/N prompt) required before continuing.
This function deletes the file(s) specified by the File prompt. Wild-card characters can be used to specify multiple files. You are prompted to confirm the deletion of each individual file which matches the file specification. If either filename or extension is unspecified, "*" is assumed. However, if the filename is terminated by a period with no following extension, this is assumed to mean an explicit extension of spaces.
Warning: You must not delete or rename a file that is loaded into the COBOL Editor: this includes its backup files (.bak) and any temporary files (.$$?). The COBOL Editor may not function correctly if any of its active files are renamed or deleted.
This function displays a list of files according to the contents of the File prompt and the List Files menu.
This renames a file. When a filename is entered at the file prompt, this function displays a second file prompt containing the same filename for editing. You can type a new name or edit the original one. The Rename menu has the options Help, Directory, and Escape.
Press Enter or repeat the rename function to rename the file with the new name.
You can move a file from one directory to another using the rename function. Edit the new filename with a different path-name for the new directory. When you complete the function, the file will be moved to the new directory.
Both the Delete and Rename functions can be used on library members. When renaming a library member, the new library name must not be longer than the original library name.
These functions are available on the List Files menu and its Control menu and on the List Directories menu.
brs displays the contents of the currently highlighted file.
You can scroll down the file but not up. The Browse menu lets you use four keys:
Key |
Function |
---|---|
<down-arrow> | Scrolls the text up one line (moves the view down one line). |
Enter | Same as <down-arrow> |
Page-Down | Scrolls the text up one page minus one line (moves the view down one page minus one line). |
Escape | Returns to the invoking menu. |
This function deletes the file at the current cursor position. You are prompted to confirm the deletion of the file.
Warning: You must not delete a file that is loaded into the COBOL Editor: this includes its backup files (.bak) and any temporary files (.$$?). The COBOL Editor may not function correctly if any of its active files are renamed or deleted.
DOS, Windows and OS/2:
This function lists the files or directories on the specified DOS,
Windows or OS/2 drive. The system prompts you to enter the new drive
letter. Make sure a disk is present in the relevant drive. An error
message is displayed if no disk is present in the drive.
Note: This function is not available under UNIX.
Escape exits from the List Files menu.
This is a toggle that lists the files in ascending or descending order according to the selected sort option (name, time, size, extension or unsorted). The state of this option appears on the information line.
list-dirs displays the List Directories menu and a listing of subdirectories.
This function redisplays the list of files in this directory. This option appears if the selected filename has any extension except .lbr.
List-catalogue appears if the selected filename is a library (extension .lbr) and displays a list of the files in the library catalogue.
For more information on libraries, see your Object COBOL User Guide.
From the List Directories menu, Select-dir, or pressing Enter returns to the File Specification menu and causes the highlighted directory to appear at the File prompt.
This function changes the current default drive and directory to the highlighted directory.
Pressing Enter returns to the File Specification menu and causes the highlighted filename to appear at the file prompt.
There is one place in the Object COBOL menu system where the behavior of this option is different. In the directory invoked from the Library Load-file menu, the select-file option immediately loads the selected file and the List-files menu remains active.
This function sorts the listing in alphabetical order by extension. For entries with the same extension, it sorts within that list alphabetically by filename. The state of this option appears on the information line.
sort-name sorts the listing in alphabetical order. The state of this option appears on the information line.
sort-size sorts the listing in size order. The state of this option appears on the information line.
sort-time sorts the listing in chronological order. The state of this option appears on the information line.
This displays the listing in an unsorted order. The state of this option appears on the information line.
This program is a specific implementation of the Name program, which enables you to invoke the Directory functions using a simple command.
Note: Where you specify the command line depends upon the operating system you are running in. For example, in Windows and OS/2, if you have created a group for COBOL, then you double click on the appropriate program icon to invoke the component. Full details on the alternative methods of invoking system tools in your environment are provided in the chapter Introduction.
To invoke the directory facility from the operating system command line, enter:
[trigger] d [filespec]
where the parameters are::
trigger |
If specified, is an executable file to run the
component in one of the available development environments, in this case
the Run-time Environment:
|
||||||
filespec |
Similar to that specified for the operating system dir
command, except that d allows multiple file extensions to be specified,
separated by commas. If filespec is omitted, *.*
is assumed for DOS, Windows and OS/2 and * is assumed for UNIX
systems. |
DOS, Windows and OS/2:
The detailed format of filespec
on DOS, Windows
and OS/2 is as follows:
[drive]:[path-name][filename][.extension[,extension]...]
UNIX:
The detailed format of filespec
on UNIX is as
follows:
[path-name][filename][.extension[,extension]...]
You can also use the d program to list the contents of a library file. Enter:
DOS, Windows and OS/2:
d lbrname.lbr\
UNIX:
d lbrname.lbr/
If lbrname.lbr
is in the current directory, d
displays the library catalog.
Copyright © 1999 MERANT International Limited. All rights reserved.
This document and the proprietary marks and names
used herein are protected by international law.
COBOL Source Information | Editor |