TOPS-20 Commands Reference Manual
Append
Adds the contents of one or more source files to the end of a new or existing destination file on disk, leaving the original source files unchanged.
Format
@APPEND (SOURCE FILE) source filespec(s) (TO) destination filespec, @@subcommand
where:
- source filespec(s)
- is a single file specification, or a series of them separated by commas.
- destination filespec
- is the specification of the destination file on disk; this can be a new file.
- @@subcommand
- means that after a final comma you can type an optional
keyword, modifying the mode or format of information
transfer.
APPEND Subcommands
(when used with the paper tape reader - PTR:)ASCII specifies that the files being appended are 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 files being appended are 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. IMAGE specifies that the files being appended are composed of 36-bit words, each consisting of one 8-bit byte; the 28 most significant bits are lost on output. IMAGE BINARY same as BINARY, but lacking the checksum. APPEND Subcommands
(when used with devices other than the paper tape reader)ASCII specifies that the files being appended are 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. IMAGE same as BINARY. IMAGE BINARY same as BINARY.
Output
As each file is appended, the system prints its specification and the word [OK]. Also, if recognition is used on the destination file specification, the system prints its status (Old generation, New generation, New file, or Superseding, for disk files; or OK, if the files are appended to a non-disk device).
Characteristics
Files Appended in Order Specified
The APPEND command attaches source files to the destination file in the order you specify them; the contents of the last specified source will appear at the end of the destination file when APPEND is finished.
Subcommands Optional
For most purposes you do not need to use subcommands when transferring information with the APPEND command. These subcommands, specifying the format of the appended files, are required only when using certain devices (for example, devices of the form MTn: (tape drives) using labeled tapes, or PTR: (paper tape reader)) or under particular conditions (for example, when transferring files over network facilities). If you are appending information from disk files or from your terminal and you do not use any subcommands, the data will be appended as written, whether in a standard format (usually ASCII or binary) or not.
Special Cases
Wildcard Characters
Wildcard characters (* and %) can be used in source file specifications only. The files are then appended in alphabetical order.
Appending Information from your Terminal
If you type TTY: in place of source file specifications, the system appends any characters you then type (after completing the command itself), until you give a CTRL/Z to return your terminal to TOPS-20 command level. CTRL/U, CTRL/R, CTRL/W, and the Delete key can be used to edit the current line of terminal input.
Restrictions
Source Files With Differing Formats
You can use the APPEND command to transfer data from a magnetic tape, terminal, card reader, paper tape reader, or other device to disk files, but if source files written in differing formats are specified within the same command, some data can be lost in the transfer.
Mixing Sequenced and Unsequenced Files
Source files created by the EDIT program should not contain sequence numbers when they are appended. Mixing files that contain sequence numbers with files that do not will cause EDIT to function improperly if used on the resulting file.
Appending to Archived Files
You can append the contents of an archived file to another file, by specifying it as the first (or source) argument of an APPEND command. You can then edit the resulting file, because it does not gain archive status although part of its contents are the same as those of the archived file; the archived file remains unchanged. However, you cannot give the specification of an archived file as the second (or destination) argument of an APPEND command, as this would change the file's contents.
Related Commands
| COPY | for making copies of files |
Examples
- Use the APPEND command to join two files.
@APPEND FORT.FOR FIL.FOR FORT.FOR.8 [OK]
- Append two files to the end of a third file.
@APPEND FORT.FOR, GORT.FOR GIL.FOR FORT.FOR.8 [OK] GORT.FOR.6 [OK]
- Access a directory and append a file from it to a file
in your connected directory.
@ACCESS <MANUALS> Password:___ @APPEND <MANUALS>REL3A.MEM REL3A.MEM <MANUALS>REL3A.MEM.4 [OK] @END-ACCESS <MANUALS>
- Use a wildcard character (%) to append several files to the end of another file.
- Use a wildcard character with the APPEND command to
create a new file.
@APPEND *.TXT BACKUP.TXT MAIL.TXT.1 [OK] NEWRUN.TXT.1 [OK] NX.TXT.1 [OK]
- Append a message from your terminal to the beginning of
the file created in Example 5. Use the symbolic generation
number -1 to specify this action.
@APPEND TTY:,BACKUP.TXT BACKUP.TXT.-1 TTY: !THIS IS A BACKUP FILE FOR ALL TEXT FILES. ^Z BACKUP.TXT.1 [OK]
@APPEND %ORT.FOR HIL.FOR FORT.FOR.8 [OK] GORT.FOR.6 [OK] HORT.FOR.3 [OK] MORT.FOR.2 [OK]