logy

#!/usr/bin/env bash

# Source this from a script to capture and `tee` standard error and standard 
# out to a log file. Calling script must source this script.  For Example:
#
# . /usr/bin/logy /var/log/project/$0.log
#
# The logging uses >(process substitution). Process substitution is supported 
# in shells like bash and zsh but is not supported in sh.

_LOG=${1?log file}
test $# -eq 1 || exit 1

mkdir -p "$(dirname "$_LOG")"

# Append stdout and stderr to log file
exec > >(
  echo -e "START\t$(date)" >> "$_LOG"
  tee -a "$_LOG"
  echo -e "END\t$(date)" >> "$_LOG"
) 2>&1