problem with if/while statement


 
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# 1  
Old 03-25-2009
problem with if/while statement

I'm trying to have the script check if a file has data or not, and then process it accordingly. If the file is empty, I want it to return "nothing to do", if not, I want it to process the file line by line. This is what I have so far, but it always returns "nothing to do", even if the file is not empty. Any ideas?

Code:
 
system "rm file2";
open(FILE2, ">file2");
 
open(MYINPUTFILE, "file");          
 
if ( ! -s file ){
 print file2 "Nothing to do\n";
 } else {
 while(<MYINPUTFILE>) {
  my($line) = $_;
  chomp($line);
  print file2 "$line\n";
  print file2 "you need to do this\n";
  print file2 " \n";
 }
}

# 2  
Old 03-25-2009
Would it not just be

if ( -s file ){

as the -s means if the file is not empty.. would using the ! not cancel that out?
# 3  
Old 03-25-2009
this is what man page says.....
-s FileName
Returns a True exit value if the specified FileName exists and has a size greater than 0.
# 4  
Old 03-25-2009
Quote:
Originally Posted by Jazmania
Would it not just be

if ( -s file ){

as the -s means if the file is not empty.. would using the ! not cancel that out?

You are correct, however, I already attempted that and swapped my "if" and "else" conditions, but I always got an error about the "else" line having a syntax error, see code and errors below.

if ( -s file ) {
while(<MYINPUTFILE>) {
my($line) = $_;
chomp($line);
print FILE2 "$line\n";
print FILE2 "You need to do this\n";
print FILE2 " \n";
}
else
{
print FILE2 "Nothing to be done\n";
}
}





syntax error at ansipre3 line 51, near "else"
syntax error at ansipre3 line 55, near "}"

Last edited by ddrew78; 03-25-2009 at 03:03 PM..
# 5  
Old 03-25-2009
how about
using :
Quote:
print "Nothing to do\n";
instead of :
Quote:
print file2 "Nothing to do\n";
don't know much about perl , it worked for me.Smilie
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