e

#!/bin/sh
# SH FILE: e
#
# Purpose   : Start Emacs in terminal mode.  Support multiple environments
# Created   : Wednesday, May 22 2024.
# Author    : Pierre Rouleau <prouleau001@gmail.com>
# Time-stamp: <2024-12-18 22:57:40 EST, updated by Pierre Rouleau>
# ----------------------------------------------------------------------------
# Module Description
# ------------------
#
# Launch emacs inside the current terminal shell in terminal mode.
# Prompt if being launched from inside an Emacs shell/terminal buffer.
#
# Note: if you want to execute the script under sudo, you will most likely
# need to provide the exact path to the script.

# ----------------------------------------------------------------------------
# Dependencies
# ------------
#
# - Emacs must be installed, accessible as 'emacs'.
# - That version of Emacs must support the terminal mode with the `-nw`
#   command line option.
# - Additionally, under macOS, no NOT use the cocoa/GUI built version of Emacs;
#   it will work but it takes much more time to start, probably loading GUI library
#   files not needed by the terminal mode version of Emacs.
#

# ----------------------------------------------------------------------------
# Code
# ----
#
#

# Check if already inside Emacs and prompt whether to continue

prompt_yn_return=
prompt_yn()
{
    # Arg 1: string prompt
    while true; do
        printf "%s [yn]? " "$1"
        read -r yn
        case $yn in
            [Yy]* )
                prompt_yn_return=y
                break
                ;;
            [Nn]* )
                prompt_yn_return=n
                break
                ;;
            * ) echo "Please answer yes or no.";;
        esac
    done
}

if [ -z "$INSIDE_EMACS" ]; then
    emacs -nw "$@"
else
    printf -- "ALREADY inside Emacs!\n"
    prompt_yn "Invoke another terminal-based Emacs inside this Emacs shell anyway"
    if [ "$prompt_yn_return" = "y" ]; then
        emacs -nw "$@"
    else
        exit 1
    fi
fi

# ----------------------------------------------------------------------------