04-13-2002
Several ways, of course. One popular way is:
var2=`echo $var1 | cut -c1-3`
and some will pipe it through sed, but I prefer to use expr because it is just one command, no pipe:
var2=`expr "$var1" : "\(...\)"`
Whatever command to use, we are "nesting" the command string in back-quotes. The back-quoted command will be replaced in the command line by its output.
In ksh, I think the most efficient way (do man ksh), when you can use it:
var2=${var1#pattern} (remove one occurent from front)
var2=${var1##pattern} (remove mult occurrences from front)
var2=${var1%pattern} (remove one occurrence from end)
var2=${var1%%pattern} (remove mult occurrences from end)
But in this case, we want to remove, from the end, all but the first 3 characters, and I could not come up with an expression to represent that.
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