Equivalent of __FILE__ and __LINE__ in Bash

Question

Is there any variable in bash that contains the name of the .sh file executed? The line number would be great too.

I want to use it in error messages such as:

echo "ERROR: [$FILE:L$LINE] $somefile not found"

Answer 1

#!/bin/bash

echo $LINENO
echo `basename $0`

$LINENO for the current line number $0 for the current file. I used basename to ensure you only get the file name and not the path.

UPDATE:

#!/bin/bash

MY_NAME=`basename $0`

function ouch {
   echo "Fail @ [${MY_NAME}:${1}]"
   exit 1
}

ouch $LINENO

You have to pass the line as a parameter if you use the function approach else you will get the line of the function definition.

Answer 2

I find the "BASH_SOURCE" and "BASH_LINENO" built-in arrays very useful:

$ cat xx
#!/bin/bash

_ERR_HDR_FMT="%.23s %s[%s]: "
_ERR_MSG_FMT="${_ERR_HDR_FMT}%s\n"

error_msg() {
  printf "$_ERR_MSG_FMT" $(date +%F.%T.%N) ${BASH_SOURCE[1]##*/} ${BASH_LINENO[0]} "${@}"
}

error_msg "here"


error_msg "and here"

Invoking xx yields

2010-06-16.15:33:13.069 xx[11]: here
2010-06-16.15:33:13.073 xx[14]: and here

Answer 3

You just need to

echo $LINENO
echo $(basename $0)

Answer 4

Here's how to do it in a reusable function. if the following is in a file named script:

#!/bin/bash
debug() {
  echo "${BASH_SOURCE[1]##*/}:${FUNCNAME[1]}[${BASH_LINENO[0]}]" > /dev/tty
}
debug

This produces the output:

script:main[5]    

Which indicates the line on which debug was called.

---

The following will print out the filename, function, line and an optional message.

Also works in zsh for extra goodness.

# Say the file, line number and optional message for debugging
# Inspired by bash's `caller` builtin
# Thanks to https://unix.stackexchange.com/a/453153/143394
function yelp () {
  # shellcheck disable=SC2154  # undeclared zsh variables in bash
  if [[ $BASH_VERSION ]]; then
    local file=${BASH_SOURCE[1]##*/} func=${FUNCNAME[1]} line=${BASH_LINENO[0]}
  else  # zsh
    emulate -L zsh  # because we may be sourced by zsh `emulate bash -c`
    # $funcfiletrace has format:  file:line
    local file=${funcfiletrace[1]%:*} line=${funcfiletrace[1]##*:}
    local func=${funcstack[2]}
    [[ $func =~ / ]] && func=source  # $func may be filename. Use bash behaviour
  fi
  echo "${file##*/}:$func:$line $*" > /dev/tty
}