12-11-2012
Not really, no. There is no seamless 'insert' operation for a file. To add extra data to the middle of a file, you must rewrite all the data that comes after it. That is why inserting data is so complicated, you never really do so.
The usual solutions for doing it all in one step, ed or sed -i, still use a temp file in many implementations.
So, since your records aren't fixed-width, the answer is no. If they were fixed-width, you could change any record without changing the length of the line, making it more possible, but fixed-width records are a difficult thing to handle in shell!
Last edited by Corona688; 12-11-2012 at 12:09 PM..
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LEARN ABOUT REDHAT
update
update(n) Tcl Built-In Commands update(n)
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NAME
update - Process pending events and idle callbacks
SYNOPSIS
update ?idletasks?
_________________________________________________________________
DESCRIPTION
This command is used to bring the application ``up to date'' by entering the event loop repeatedly until all pending events (including idle
callbacks) have been processed.
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The update idletasks command is useful in scripts where changes have been made to the application's state and you want those changes to
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so update idletasks will cause them to run. However, there are some kinds of updates that only happen in response to events, such as those
triggered by window size changes; these updates will not occur in update idletasks.
The update command with no options is useful in scripts where you are performing a long-running computation but you still want the applica-
tion to respond to events such as user interactions; if you occasionally call update then user input will be processed during the next
call to update.
SEE ALSO
after(n), bgerror(n)
KEYWORDS
event, flush, handler, idle, update
Tcl 7.5 update(n)