TOPS-20 Commands Reference Manual
COPY
Creates a copy of a file.
Format
@COPY (FROM) source filespec (TO) destination filespec, @@subcommand
where:
| source filespec | is the specification of the file or device whose contents you want to copy. | ||||||||||
| destination filespec | is the specification of the file or device in which you want to store a copy of the file. Default - same as source filespec but in your connected directory, if necessary using the next higher generation number | ||||||||||
| @@subcommand | means that after a final comma you can specify the mode and format of the transfer with one of the following subcommands: |
| ASCII | specifies that the file being copied is written in ASCII mode, with 36-bit words each consisting of five 7-bit bytes and a parity bit; the parity bit means that the eighth hole of the paper tape is never punched. |
| BINARY | specifies that the file being copied is composed of 36-bit words, each consisting of six 6-bit bytes with the seventh hole of the paper tape set always to 0 and the eighth hole set always to 1; causes a checksum calculation. |
| BYTE n | specifies that the byte size of the destination file is to be n (any decimal number). If you do not give the BYTE subcommand, the destination file will have the same byte size as the source file. See also Hints - Viewing Display Screen Data below. |
| IMAGE | specifies that the file being copied is composed of 36-bit words, each consisting of one 8-bit byte; the 28 most significant bits are set to 0 on input and are lost on output. |
| IMAGE BINARY | same as BINARY, but lacking the checksum |
COPY Subcommands
(when used with devices other than the paper tape reader or paper tape
punch)
| ASCII | specifies that the file being copied is written in ASCII mode, with 36-bit words each consisting of five 7-bit bytes and a parity bit; the parity bit means that the least significant bit is set to 0 on input and is lost on output. | ||||||||||
| BINARY | calls for a direct transfer of data in 36-bit bytes. | ||||||||||
| BYTE n | specifies that the byte size of the destination file is to be n (any decimal number). If you do not give the BYTE subcommand, the destination file will have the same byte size as the source file. See also Hints - Viewing Display Screen Data, below. | ||||||||||
| IMAGE | same as BINARY. | ||||||||||
| IMAGE BINARY | same as BINARY. | ||||||||||
|
sets the condition under which COPY overwrites the destination file of
the same name.
|
Output
As each file is copied, the system prints the specifications of the source and destination files and the word [OK]. The delay before you see this [OK] indicates how long it took to copy the file. If you use recognition on the destination file specification, the system prints, !New Generation!, !New File!, or !Superseding!, to indicate the status of disk files, or !OK!, if the file is copied to a non-disk device.
Characteristics
Optional Subcommands With Paper Tape
Each subcommand, when used to copy information from the paper tape reader (PTR:), specifies an interpretation of eight-bit bytes, represented as eight-hole lines on paper tape. When used with the paper tape punch (PTP:), each subcommand specifies a mapping of information to the eight-bit bytes of paper tape.
Optional Subcommands With Other Devices
Each subcommand can be used under particular conditions, for example, when transferring files over network facilities (using DCN: and SRV:),to specify the byte size of information being copied. In general, you can use COPY command subcommands whenever you need to specify the byte size of information being copied.
Hints
RENAME Faster Than COPY for Transferring Files
For moving a set of files from one directory to another on the same structure, the RENAME command is a faster and more efficient means than COPY. This is because RENAME only changes the file specifications; it does not copy the contents of the files. Also, a file transfer with the RENAME command leaves only one set of files, while a transfer with the COPY command leaves two sets: the original copies and the destination copies. The original copies are often unnecessary and must be deleted.
Using Devices as Source and/or Destination Filespecs
By specifying a device as the source and/or destination filespec, you can use the COPY command to transfer information between card- or paper-tape-handling devices, magnetic tape drives, line printers, terminals, or other output devices. However, the PLOT, PRINT, PUNCH and TYPE commands, and appropriate utility programs (such as DUMPER and EDIT), offer more flexibility for most applications.
Copying To or From TTY:
You can simulate the action of the CREATE command for creating files by copying from device TTY: to a new filespec, ending your input with a CTRL/Z; use CTRL/U, CTRL/R, CTRL/W, and the DELETE key to edit the current line of terminal input. You can simulate the action of the TYPE command for displaying files by copying from an existing filespec to device TTY:.
Viewing Display Screen Data
If you specify TTY: as the destination filespec and then give the BYTE 8 subcommand, characters in the source file will be sent literally to your terminal. Do this to examine special display screen data (for 8-bit ASCII files only).
Erasing the Contents of a File While Keeping the Filespec
You can erase the contents of a file by copying from device NUL: to the file. NUL: is a receptacle for unwanted program output and a supplier of null input.
Spooled Output Action
If you send information to output devices using the COPY command, your request is processed according to the status of the SPOOLED-OUTPUT-ACTION parameter, which you set with the SET SPOOLED-OUTPUT-ACTION command.
Using Wildcards in Source and/or Destination Filespecs
You can use wildcard characters (* and %) in source and/or destination filespecs to copy many files at a time. Default values will be assumed for filespec fields you do not specify. Note that if you use wildcard characters to copy more than one source file into a single destination file on disk, the contents of each source file will appear in a different generation of the destination file; the highest generation will contain a copy of the last source file only. Use the APPEND command to put the contents of several files into a single file.
Specifying a New Account or Protection Number
The COPY command lets you specify the new file's protection number, and the account to which storage fees for it will be charged. Follow the new file specification with a semicolon (;) and the letter P before giving a new 6-digit protection number, and with a semicolon and the letter A before giving a new account (which must be valid for your user name). If you do not specify an account for a new file, it will take as a default the account you gave in your most recent LOGIN or SET ACCOUNT command. However, non-default protection numbers will be maintained for higher generations of existing files, unless you specify otherwise in the COPY command that creates that higher generation.
Restrictions
Copying Archived Files
You can make a copy of an archived file by specifying it as the first (or source) argument in a COPY command, and specifying a file of different name or type as destination. You can edit the new file, because it does not have archive status although it has the same contents as the original file. However, you cannot give the specification of an archived file as the second (or destination) argument of a COPY command, as this would replace the file's contents. If you attempt to do so, whatever source argument you supply will be copied into the next higher generation of the archived file, leaving the archived file intact. And, if you include the generation number when specifying an archived file as the second argument of a COPY command, the command will fail.
Warning
Destroying the Previous Contents of Files
If you give a destination file specification that includes a generation number, the source file will be copied into that file, replacing any previous contents if that generation of the file already exists. Those contents cannot be recovered. But see Restrictions - Copying Archived Files, above.
Related Commands
| APPEND | for adding information to a file or putting the contents of many files into a single file |
| RENAME | for changing only the specification of a file |
| SET SPOOLED-OUTPUT-ACTION | for changing the setting of the SPOOLED-OUTPUT-ACTION parameter, which determines when files copied to output devices are processed |
| DIRECTORY with the TIMES WRITE subcommand and VD | for displaying the date and time that the file was written |
Examples
- Make an extra copy of a file in your connected directory.
@COPY FORT.TXT BACKUP.TXT FORT.TXT.1 => BACKUP.TXT.3 [OK]
- Copy a file from your directory into another user's directory, allowing
the destination file to be labeled with default file specification (the
source file specification).
@ACCESS <SARTINI> Password:___ @COPY TEST1.CBL <SARTINI> TEST1.CBL.2 => <SARTINI>TEST1.CBL.2 [OK] @END-ACCESS <SARTINI>
- Use a wildcard character to copy several files from your directory on
another structure to magnetic tape.
@ACCESS SNARK: @COPY SNARK:NA*.TST MT2: SNARK:NACCESS.TST.2 => MT2:NACCESS.TST [OK] SNARK:NADVISE.TST.2 => MT2:NADVISE.TST [OK] SNARK:NAPPEND.TST.2 => MT2:NAPPEND.TST [OK] SNARK:NASSIGN.TST.2 => MT2:NASSIGN.TST [OK] SNARK:NATTACH.TST.2 => MT2:NATTACH.TST [OK] @END-ACCESS SNARK:
- Use the COPY command to create a short text file.
@COPY TTY: NEW-FILE.TXT TTY: => NEW-FILE.TXT.2 THIS FILE WAS CREATED USING THE COPY COMMAND. ^Z @ @TYPE NEW-FILE.TXT THIS FILE WAS CREATED USING THE COPY COMMAND.
- Copy a file from your directory into another user's directory. Give
the SUPERSEDE NEVER subcommand to cancel the COPY command if the other user
already has a copy of the file.
@ACCESS <STEVENS> Password:___ @COPY STATS.TXT <STEVENS>, @@SUPERSEDE NEVER @@ STATS.TXT.1 => <STEVENS>STATS.TXT.3 %Not superseding current file