Dear All,

I have one file which looks like :

account1asswd1
account2asswd2
account3asswd3
account1asswd4
account5asswd5
account6asswd6

you can see there're two records for account1. and is there any shell command which can find out : account1 is the duplicate record in file?

Thanks.

awk -F":" '{_[$1]++}
END{
  for (i in _)
   print "Duplicated: _[i]
}' filename

i guess there's one missing " in 4th line?
but after appending the " , it still doesn't work...