How to do what head, tail, more, less, sed do in Powershell? [closed]

Get-Content (alias: gc) is your usual option for reading a text file. You can then filter further:

gc log.txt | select -first 10 # head
gc -TotalCount 10 log.txt     # also head
gc log.txt | select -last 10  # tail
gc -Tail 10 log.txt           # also tail (since PSv3), also much faster than above option
gc log.txt | more             # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' }         # sed

This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow.

The PowerShell Community Extensions include some cmdlets for specialised file stuff (e.g. Get-FileTail).