Bash logging including line number

Hope below example with shopt -s expand_aliases and alias could help:

try.sh

#! /usr/bin/env bash

shopt -s expand_aliases

# =============================================================
# Define the logger
# =============================================================
alias logger='logger_function [${BASH_SOURCE##*/}] [$FUNCNAME] [$LINENO] '

logger_function()
{
    echo $@
}

# =============================================================
# Use the logger
# =============================================================
my_function()
{
    logger "hello world!"
}

my_function

Test result in: GNU bash, version 3.2.57(1)-release

$ ./try.sh
[try.sh] [my_function] [20] hello world!

Considering the question is emphasizing on: line number, so in this example, the exactly same input and output of the question are not used.

But to make it more informative, the logging utility definition is added with:

• $BASH_SOURCE
• $FUNCNAME
• $LINENO

So, it can print the file name, function name and line number.

Regarding to alias usage here, it looks like but isn't really comparable to a C macro according to: https://tldp.org/LDP/abs/html/aliases.html

You are better off using the BASH_LINENO array. Here is the extract from Bash Manual:

BASH_LINENO An array variable whose members are the line numbers in source files where each corresponding member of FUNCNAME was invoked. ${BASH_LINENO[$i]} is the line number in the source file (${BASH_SOURCE[$i+1]}) where ${FUNCNAME[$i]} was called (or ${BASH_LINENO[$i-1]} if referenced within another shell function). Use LINENO to obtain the current line number.

Here is a comprehensive logging implementation for Bash:

https://github.com/codeforester/base/blob/master/lib/stdlib.sh