CTSS: Commands

LOGIN is the only command available when you first connect to CTSS. It is also treated as a user level command so you can use it to switch accounts when logged in.

TTPEEK will show how much CPU time and disk space you have used. A quota for this was established when a user ID was created.

DIAL allows a non logged in terminal to be associated with a logged in session. Once associated it can be used by programs on the logged in session to send and receive text, but cannot run commands directly. However none of the existing commands on CTSS use this facility.

HELLO gives a simple system summary similar to what you see at login.

SUBSYS and OPTION restrict what type of operations can be done. It seems to be intended as a way for a login to be used to run a specific interactive program rather than issue general commands. These are selected by the user and can be changed so it is not a security mechanism.

A sample of WHO output:

who
W 1815.0
        
MIT8C0 STARTED AT 1127.2 02/15.
                               
 2  USERS AT  1815.0 02/15.
                           
LINE   USER     NAME  GRP UNIT  TUSED TIMEON
 1 C0056 99995 FIBMON  0 (FIB)     .0 1127.2 02/15
 3 M1416    10  ELIZA  1 700000    .0 1815.0      
                                            
R .016+.016

These have been discussed in the post Files and directories.

The exception is CALL, which is a thin wrapper around several system calls. For example to delete a file A MAD you could use CALL DELFIL A MAD.

P is a good choice to view any type of text file.

These are all line-orientated editors. The ED family shares a very similar command set, documented on the ED page. QED is a more sophisticated editor allowing multiple buffers; it was created by Ken Thompson of Unix fame. These will be looked at in a lter post.

These exist to translate between text formats and to save space.

We looked at SQUASH and XPAND in the post Files and directories.

CRUNCH was used with the BEFAP assembler which is also not available.

SQZBSS and PADBSS works on BSS object files by removing card sequence numbers and compressing sequences of zero value words.

ARCHIV is reminiscent of Unix tar, bundling a number of files into a single file so it takes up less space (both in terms of disk and entries in the directory) and can be un-archived later. Its first argument is a command like C for create and X for extract, also implying that tar was modelled on this. The semantics were a bit different as it generally worked on files with the same name2. For example, if you wanted to archive files A MAD B MAD and C MAD into an archive ARC MAD you would type archiv arc mad a b c.

APND is used as follows:

APND sub mad main main

which will append a copy of SUB MAD to the end of MAIN mAD.

APEND is similar but takes multiple files as input and writes to the first file as output, so to get SUB1 MAD and SUB2 MAD appended to MAIN MAD you would do:

APEND main mad sub1 mad sub2 mad

COMBIN is useful for card image files as it can adjust the seqeunce numbers of the combined file to make them contiguous. It is also used to create a libary from several BSS files.

We looked at these in the post Files and directories.

RUNCOM will run a series of commands stored in a file.

The FIB commands allow you to queue a job to be run the next time you are logged out.

Both of these will be discussed in a later post.

ECHO is like the Unix shell set -x in that it prints its arguments and then executes them as a command.

We'll look at these in the next post.

PINFO appears to be like the Unix man command, showing text files about each command on the system. Both PINFO and its files are not available on the CTSS we have.

None of these commands are available on the CTSS we have today. Most deal with typewriter control.

PRNTER appears to be used to debug issues communicating with a typewriter.

REMARK allows a user to send comments to the operators: these are appended to a public file and was then printed out once a day.

I welcome any questions or comments, and also especially any corrections if I have got something wrong. Please email me at rupert@timereshared.com