System information

2.1.5 Memory Buffer Operation

When ED begins, the memory buffer is empty. You can either append lines from the source file

with the A command, or enter the lines directly from the console with the insert command. The

insert command takes the following form:

ED then accepts any number of input lines. You must terminate each line with a <cr> (the <If >

is supplied automatically). A single CTRL-Z, denoted by an up arrow (T)Z, returns ED to

command mode. The CP is positioned after the last character entered. The following sequence:

I <cr>

NOW IS THE<cr>

TIME FOR<cr>

ALL GOOD MEN<cr>

leaves the memory buffer as

NOW IS THE<cr><If>

TIME FOR<cr><If>

ALL GOOD MEN<cr> <If>

Generally, ED accepts command letters in upper- or lower-case. If the command is upper-case,

all input values associated with the command are translated to upper-case. If the I command is

typed, all input lines are automatically translated internally to upper-case. The lower-case form of

the i command is most often used to allow both upper- and lower-case letters to be entered.

Various commands can be issued that control the CP or display source text in the vicinity of the

CP. The commands shown below with a preceding n indicate that an optional unsigned value can

be specified. When preceded by +-, the command can be unsigned, or have an optional preceding

plus or minus sign. As before, the pound sign # is replaced by 65535. If an integer n is optional,

but not supplied, then n=1 is assumed. Finally, if a plus sign is optional, but none is specified,

then + is assumed.

2.1 Introduction to ED CP/M Operating System Manual

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