Why lf is the best TUI file manager

• written in Go - compiled, cross-platform, simple, single binary. even on a minimal OS, you just need to curl the binary from Github releases, extract the tar.gz, and you can immediately use it.

• Vim key bindings out of the box. including things like marks.

• client-server model. no need for tabs, just open multiple terminals/tmux splits/whatever with lf instances and copy-paste between them.

• uses the XDG specification by default.

• keeps track of selected files in a simple way. ~/.local/share/files: first line is mode (move/copy), rest are filenames. you determine the separator.

• configurable in shell. which really just means configurable in any language. want to do shell script only? fine. want to call out to a program in Python that interfaces with a Rust library? fine. want to use a perl one-liner? fine. also, you choose the shell. as long as it’s POSIX-compatible.

• here’s how powerful it is. Want to create a transient C program that gets compiled on the fly and then removed? Sure:

  cmd crazy_command !{{
    execfile="$(mktemp)"
    trap 'rm $f' INT TERM EXIT
  
    cc -x c -o "$execfile" - <<'EOF' \
      && "$execfile" $fx
  
    #include <stdio.h>
    #include <string.h>
    int main(int argc, const char *argv[]) {
      printf("Running as %s\n", argv[0]);
      printf("argnum\tfname length\tfname\n");
      for (unsigned long i = 1; i < argc; ++i) {
        printf("%lu\t%lu\t%s\n", i, strlen(argv[i]), argv[i]);
      }
    }
    EOF
    rm "$execfile"
    trap - INT TERM EXIT
  }}
  

  Or let’s say you have an nginx log like this and select it:

172.31.15.176 - - [03/Oct/2019:06:54:09 +0000] "GET / HTTP/1.1" 200 5127 "-" "ELB-HealthChecker/2.0"
172.31.41.111 - - [03/Oct/2019:06:54:55 +0000] "GET /api/dataset/csv HTTP/1.1" 401 15 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/77.0.3865.90 Safari/537.36"
172.31.15.176 - - [03/Oct/2019:07:03:00 +0000] "GET / HTTP/1.1" 499 0 "-" "ELB-HealthChecker/2.0"

You can create a function to visualize all response codes with an image from http.cat:

cmd lookup_code ${{
    tmp=$(mktemp)
    trap 'rm $tmp' INT TERM EXIT
    grep '"GET ' $f \
    | cut -d'"' -f3 \
    | cut -d' ' -f2 \
    | while read -r code; do
      curl -sL https://http.cat/"$code" -o "$tmp" \
        && sxiv $tmp >/dev/null 2>&1
      done

    rm "$tmp"
    trap - INT TERM EXIT
}}