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PERUSE command

The PERUSE command allows you to read a file  using  read-only  editor
commands.


Format

     @PERUSE (FILE) /switch(es) filespec

     where:

     /switch(es)    are keywords that apply to the EDIT  editor.   For
                    descriptions of these switches, see the /CREATE or
                    EDIT commands.

     filespec       is the name of the file you want to read.
                         Default - the  last  file  specification  and
                                   associated  switches  you gave in a
                                   CREATE,  EDIT,  or  PERUSE  command
                                   during the current terminal session

Characteristics

     The PERUSE command runs the  EDIT  system  program  in  read-only
     mode.   (However,  see Special Cases - Using an Editor Other than
     EDIT, below.) PERUSE is actually the same as the  EDIT  /READONLY
     command.   In  EDIT  /READONLY mode you can use only EDIT program
     switches and commands that do not modify the file.


Hints

     Avoid Accidental File Modification

          Use PERUSE when  it  is  important  to  avoid  the  risk  of
          accidentally modifying a file.


     PERUSE Line in SWITCH.INI

          Add a line to your SWITCH.INI file for use with  the  PERUSE
          command.


Special Cases

     Using an Editor Other than EDIT

          The CREATE, EDIT and PERUSE commands in this  manual  assume
          that  these  commands call on the program EDIT.  If your job
          uses another editing program, for example, EDT, the switches
          and examples shown here will not be applicable.

          The Editor used by the CREATE, EDIT and PERUSE  commands  is
          specified by the logical name EDITOR:.  You can find out the
          name of this program  by  giving  the  command,  INFORMATION
          LOGICAL-NAMES  EDITOR:.   The  job-wide  definition (if any)
          will be given first, followed by the system-wide definition;
          the  job-wide  definition  prevails  if  both exist.  If the
          definition of EDITOR:  is SYS:EDIT.EXE, the CREATE, EDIT and
          PERUSE  commands  will function as described in this manual.
          Otherwise, you must  consult  the  appropriate  manual  (for
          example, the EDT-20 Reference Manual) for information.


Restrictions

     Listing Available EDIT Read-Only Switches and Commands

          Many of the EDIT switches and commands that are displayed in
          response  to  a  ?  modify the file and do not function with
          PERUSE.  If you give a file-modifying switch, the switch  is
          ignored  but  no  error message is displayed.  If you give a
          file-modifying  EDIT  command,  you  receive   the   message
          %ILLEGAL COMMAND.

          For further information on these switches and  commands  see
          the EDIT Reference Manual.


Effect on Memory

     The PERUSE command clears any  unkept  forks  from  memory,  then
     loads your edit program.


Related Commands

     CREATE                        for creating new files

     DIRECTORY-class commands      for getting lists of existing files

     EDIT                          for modifying files

     TYPE                          for printing files on your terminal


Examples

     1.  PERUSE a file

         @PERUSE FILEX.FOR
         Read: FILEX.FOR.1
         *P
         00100  !THIS IS FILEX.FOR

     2.  PERUSE a file, ten lines at a time, and begin at line 100.

         @PERUSE /PLINES:10 FIND.BAS
         Read: FIND.BAS
         *P 100
         00100   !       ADD ROUTINE
         00200   FOR X = 0 TO 400
         00300   IF X$(X) = "XXX" THEN GOTO 2050
         00400   NEXT X
         00500   PRINT STRING$(10,10);"FILE FULL"\SLEEP 4\GOTO 199
         00600   PRINT E$ \LINPUT"ENTER THE NAME ";M$
         00700   IF M$ <> "" THEN LET X$(X) = M$ ELSE GOTO 199
         00800   PRINT E$ \LINPUT"ENTER THE NUMBER ";O$
         00900   IF O$ <> "" THEN LET Y$(X) = O$ ELSE GOTO 199
         01000   PRINT E$\INPUT"MORE NAMES TO ENTER ";D$
         *E