Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

Empty file check

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Empty file check
# 1  
Old 02-26-2014
Empty file check
Hi gurus ,


I have two files and i want to perform different action based on the condition if both or either is empty

HTML Code:
If [ File 1 is not empty && File two is not empty ]
 then 
 Do something 
 elif [ file 1 is empty && file 2 is not empty ]
 then 
 do something 
 elif [ file 1 is not empty && file 2 is empty ]
 then 
 do something 
 else 
 do something
 fi
I have tried the below bt its not working. only the first condition is getting evaluated
Code:
 if [[  -s "$f1"  && -s "$f2" ]]
 then
 echo " Both not empty"
 elif [[ ! -s "$f1"  && -s "$f2" ]]
 echo "First file empty and second not empty"
 elif [[  -s "$f1"  && ! -s "$f2" ]]
 echo "Fist file not empty and second file empty"
 else
 echo " Both Files empty"

# 2  
Old 02-26-2014
Yes the part after the && will only get evaluated if the part before the && is true. This is by design, && is not a true logical AND.


--
Also there is a syntax error, since the "then" statements were omitted.

--
Also there are the wrong quotes characters in you file! Replace them with "
Last edited by Scrutinizer; 02-26-2014 at 03:24 PM..
# 3  
Old 02-26-2014
This might help you

Code:
$ touch test1
$ cat test1
$ touch test2
$ echo 'I am not empty' >test2
$ cat test2
I am not empty

Code:
#!/bin/bash



empty(){
	for file in $(echo "$*"); do 
		[ -s  "$file"  ] || return 1
	done
}

# Call function with one empty and non empty file
empty test1 test2

if [ "$?" -eq "0" ]; then
	echo "all fine"
else
        echo "something went wrong"
fi 

# Call function with non empty files
empty test2 test2

if [ "$?" -eq "0" ]; then
	echo "all fine"
else
	echo "something went wrong"
fi

Code:
$ bash test
something went wrong
all fine

---------- Post updated at 01:35 AM ---------- Previous update was at 01:30 AM ----------

what I wanted to suggest you that create function like above according to your need and play with exit code it's easy.
# 4  
Old 02-26-2014
Or just:
Code:
if [[ -s "$f1" ]]; then
  if [[ -s "$f2" ]]; then
    echo “Both not empty”
  else
    echo "First file not empty and second file empty"
  fi
else
  if [[ -s "$f2" ]]; then
    echo "First file empty and second not empty"
  else
    echo "Both empty"
  fi
fi

# 5  
Old 02-26-2014
Correction:
Code:
if [ -s "$f1" ] && [ -s "$f2" ]
then
        echo "Both not empty"
elif [ ! -s "$f1" ] && [ -s "$f2" ]
then
        echo "First file empty and second not empty"
elif [ -s "$f1" ] && [ ! -s "$f2" ]
then
        echo "First file not empty and second empty"
else
        echo "Both Files empty"
fi

Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

To check whether the file is empty or not in shell script (sh)

Hi All, I need to check a file whether it exists and also whether it is empty or not. I have a code for this but it is not working as per my requirement. Can anyone pls suggest me on this. function funcFLSanityCheck { if then echo "${varFLSentFileListPath}/${varFLSentFileName}... (7 Replies)
Discussion started by: Arun1992
7 Replies

2. Shell Programming and Scripting

How to check if the file is empty or has blank space.?

Hi, I am using KSH. I am trying to check if the output file is empty or not. I tried with ] but what i see is my file is empty but still manages to have a size of 1 instead of 0. But my file doesnot have anything its empty. I am not sure how to check this. can any one help? (10 Replies)
Discussion started by: Sharma331
10 Replies

3. UNIX for Dummies Questions & Answers

Check if file is empty with variables, bash

Hello again! I have some trouble with scripting in bash. In the following script I read from a folder with the files line0_Ux.xy line1_Ux.xy line2_Ux.xy . . . Some of the files are empty. For those I would like to print a "0" in list. I think the problem with the code is that... (4 Replies)
Discussion started by: bjoern456
4 Replies

4. Shell Programming and Scripting

Condition to check whether configuration file is empty or not?

CMD=$(find "${Release_Container}" -iname "${Release_Name}"_Release.txt) for i in `cat $CMD` do if ];then cd ${Sandbox_dir} CMD1=$(find "${Sandbox_dir}"/* -iname "${Release_Name}" -type d | awk -F/ '{print $(NF)}' | head -1 ) if ];then echo -e "################### CHECKOUT START... (2 Replies)
Discussion started by: anuragpgtgerman
2 Replies

5. Shell Programming and Scripting

Check if a text file is empty or not (using ls -s)

Hello, I want to make a script which says if a text file is empty or not. I tried two ways of making it, but I have problems with both of them. Now I think that the better way is the ls -s solution (considering that an empty text file has a 0 weight, because "cat file.txt" fails when file is... (4 Replies)
Discussion started by: Link_
4 Replies

6. Shell Programming and Scripting

Need to check for empty file in C shell script

I am running a C shell script. I have an output file from a previous step and I need to run "something" in the next step to check if the file is empty. If the file is empty, then the job script should finish EOJ. If the file is not empty then the job script should abend. Please help Thanks. (4 Replies)
Discussion started by: jclanc8
4 Replies

7. Shell Programming and Scripting

check if file is empty

How do I check if a file is empty in a sh script I want to test in my shell script if the output file is empty and if it is do one thing and if it isnt empty do another? any ideas? (8 Replies)
Discussion started by: stolz
8 Replies

8. UNIX for Dummies Questions & Answers

to check if file is empty or not and return a non zero value

Hi All, I am new to unix worldd . I need to check a file1 if its empty or not. If its empty then return a non zero value say 99 could you pls let me know the perl script for this. (2 Replies)
Discussion started by: mavesum
2 Replies

9. UNIX for Dummies Questions & Answers

How to check if a file is empty?

Hi Masters..... I have problem !!! I need to check number of records in a file and if it is zero or file is empty i need to do some task. if ; then echo "File s empty" else echo "Not empty" fi so how to check this condition. I used wc -l < filename.txt => 1 for zero records same result... (1 Reply)
Discussion started by: shreekrishnagd
1 Replies

10. UNIX for Dummies Questions & Answers

How to check for empty file in Perl?

Hi, May I know how to check for empty file in Perl. Iam missing something, somewhere. #!/usr/bin/perl my $open_dir = '/path/'; my $file; my $ma = "abc_.*.\.psv\$" opendir(VAR, $open_dir) or die "Can't open $oepn_dir: $!\n"; while( defined ($file = readdir VAR) ) #read all... (1 Reply)
Discussion started by: deepakwins
1 Replies
Login or Register to Ask a Question