How to check if a file is empty in Bash

Question

I have a file called diff txt  I Want to check whether it is empty  I wrote a bash script something like below  but I couldn t get it work  if   -s diff txt   then         touch empty txt         rm full txt else         touch full txt         rm emtpy txt fi

User · Answer

-f filename  amp  amp    -s filename     amp  amp  echo  filename exists and is empty

User · Answer

Easiest way for checking file is empty or not   if   -s  path-to-file filename txt   then      echo  File is not empty  else      echo  File is empty  fi   You can also write it on single line     -s  path-to-file filename txt    amp  amp  echo  File is not empty     echo  File is empty

User · Answer

While the other answers are correct  using the  -s  option will also show the file is empty even if the file does not exist  By adding this additional check  -f  to see if the file exists first  we ensure the result is correct   if   -f diff txt   then   if   -s diff txt     then     rm -f empty txt     touch full txt   else     rm -f full txt     touch empty txt   fi else   echo  File diff txt does not exist  fi

User · Answer

Misspellings are irritating  aren t they   Check your spelling of empty  but then also try this      bin bash -e  if   -s diff txt   then         rm -f empty txt         touch full txt else         rm -f full txt         touch empty txt fi   I like shell scripting a lot  but one disadvantage of it is that the shell cannot help you when you misspell  whereas a compiler like your C   compiler can help you   Notice incidentally that I have swapped the roles of empty txt and full txt  as  Matthias suggests

User · Answer

To check if file is empty or has only white spaces  you can use grep   if    -z   grep      space      filename       then   echo  Empty file         fi

User · Answer

-s file    --  Checks if file has size greater than 0   if    -s diff txt     then echo  file has something   else echo  file is empty   fi   If needed  this checks all the   txt files in the current directory  and reports all the empty file   for file in   txt  do if      -s  file     then echo  file  fi  done

User · Answer

Many of the answers are correct but I feel like they could be more complete     simplistic etc  for example    Example 1   Basic if statement    BASH4  example on Linux    typeset read file   tmp some-file txt  if     -s    read file             -f    read file      then     echo  Error  file    read file   not found         exit 7 fi   if  read file is empty or not there stop the show with exit  More than once I have had misread the top answer here to mean the opposite    Example 2   As a function    -- Check if file is missing  or empty --   Globals  None   Arguments  file name   Returns  Bool   -- is file empty or missing              -f    1        -s    1       amp  amp  return 0    return 1

User · Answer

I came here looking for how to delete empty   init   py files as they are implicit in Python 3 3  and  ended up using   find -depth     -type f  -name   init   py     -print0     while IFS  read -d    -r file  do if      -s  file     then rm  file  fi  done   Also  at least in zsh  using  path as the variable also breaks your  PATH env and so it ll break your open shell  Anyway  thought I d share

User · Answer

geedoubleya answer is my favorite   However  I do prefer this  if    -f diff txt  amp  amp  -s diff txt    then   rm -f empty txt   touch full txt elif    -f diff txt  amp  amp    -s diff txt    then   rm -f full txt   touch empty txt else   echo  File diff txt does not exist  fi

User · Answer

-s file name      echo  file is empty

[linux] How to check if a file is empty in Bash?

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