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 # headgc -TotalCount 10 log.txt     # also headgc log.txt | select -last 10  # tailgc -Tail 10 log.txt           # also tail (since PSv3), also much faster than above optiongc log.txt | more             # or less if you have it installedgc 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).

Here are the built-in ways to do head and tail. Don't use pipes because if you have a large file, it will be extremely slow. Using these built-in options will be extremely fast even for huge files.

gc log.txt -head 10 gc log.txt -tail 10gc log.txt -tail 10 -wait # equivalent to tail -f

more.exe exists on Windows, ports of less are easily found (and the PowerShell Community Extensions, PSCX, includes one).

PowerShell doesn't really provide any alternative to separate programs for either, but for structured data Out-Grid can be helpful.

Head and Tail can both be emulated with Select-Object using the -First and -Last parameters respectively.

Sed functions are all available but structured rather differently. The filtering options are available in Where-Object (or via Foreach-Object and some state for ranges). Other, transforming, operations can be done with Select-Object and Foreach-Object.

However as PowerShell passes (.NET) objects – with all their typed structure, eg. dates remain DateTime instances – rather than just strings, which each command needs to parse itself, much of sed and other such programs are redundant.