Szathmáry László honlapja @ DEIK | Nim2 / The Unix `which` command

You need something like the which command, i.e. you want to figure out where a binary is in the PATH (in which directory).

import std/os
import std/strutils

proc which(fname: string): string =
let
sep = if defined(windows): ";" else: ":"
dirs = getEnv("PATH").split(sep)

for dir in dirs:
let path = joinPath(dir, fname)
if fileExists(path):
return path
#
return "" # not found

proc main() =
echo which("date") # /usr/bin/date

echo which("nim") # /home/jabba/.nimble/bin/nim

echo which("doesnt_exist") # "" (empty string)

##########

when isMainModule:
main()

If the binary is found, the function returns its full path.

If not found, then an empty string is returned.