how to trim the absolute directory path?

Question

I have a absolute path to directory halo: /pkg/check/power/halo

I want to trim the absolute path to only: /pkg/halo

how can i do that using regex or pcreCompile function or unix?

@SurabhS Switching from bash to tcl to perl to C, what are you looking for?? What's the context? Also, your _"I want to trim"_ is not clear; do you want to keep the `first` and `last` components or the ones that match `pkg` and `halo`? — Fravadona, Jan 13 '22 at 13:43

score 3 · Answer 1 · answered Jan 12 '22 at 13:38

3

When working with paths, you're strongly recommended to use file split and file join as they handle weirdnesses you're not aware of.

set path /pkg/check/power/halo
set pieces [file split $path]
set result [file join {*}[lrange $pieces 0 1] [lindex $pieces end]]

Or (removing pieces rather than selecting them):

set result [file join {*}[lreplace $pieces 2 end-1]]

answered Jan 12 '22 at 13:38

Donal Fellows

Fravadona · Answer 2 · 2022-01-12T12:44:41.100

2

With tcl:

set path "/pkg/check/power/halo"
set path [ split $path / ]
set path /[lindex $path 1]/[lindex $path end]

edited Jan 12 '22 at 12:44

answered Jan 12 '22 at 12:38

Fravadona

Maybe use `file split` and `file join` to better handle any odd stuff that might come up with real paths? – Shawn Jan 12 '22 at 13:08
can you have any expamle @Shawn – Surabh S Jan 12 '22 at 13:10
@SurabhS `set parts [file split $path]; puts [file join {*}[lreplace $parts 2 end-1]]` – Shawn Jan 12 '22 at 13:38

2 Answers2