Edlin: W (Write)--Notes
How the W command works
When you open a file, Edlin reads lines from disk until memory is more than
75-percent full. It reserves the other 25 percent for changes you might make to
the text. If your entire file fits in memory, Edlin displays the following
End of input file
If you see this message, you do not need to use the w and a (append) commands.
If Edlin does not display this message when you open a file, the size of the
file exceeds available memory. Therefore, you must edit your file in stages by
using the w and a commands to write and read parts of the file, respectively.
The w command does not write to disk the changes you make unless it was actually
necessary to use the w command. Therefore, if you use the w command even though the whole file fit into memory and then you use the q (quit) command to quit Edlin, none of the changes you made to the file are
After Edlin writes the first portion of the edited file from memory to a disk,
you can use the Edlin l (list) command at the Edlin prompt to see the correctly renumbered lines that
remain, beginning with line number 1.
If you omit the n parameter, Edlin writes lines from the edited file in memory to a disk until
memory is 25-percent full.
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