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)
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)
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)
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)
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)
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)
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 $(NF)}' | head -1 )
if ];then
echo -e "################### CHECKOUT START... (2 Replies)
Hello again!
I have some trouble with scripting in bash.
In the following script I read from a folder with the files
line0_Ux.xy
line1_Ux.xy
line2_Ux.xy
.
.
.
Some of the files are empty. For those I would like to print a "0" in list.
I think the problem with the code is that... (4 Replies)
Hi,
I am using KSH.
I am trying to check if the output file is empty or not.
I tried with ] but what i see is my file is empty but still manages to have a size of 1 instead of 0.
But my file doesnot have anything its empty.
I am not sure how to check this.
can any one help? (10 Replies)
Hi All,
I need to check a file whether it exists and also whether it is empty or not. I have a code for this but it is not working as per my requirement. Can anyone pls suggest me on this.
function funcFLSanityCheck
{
if
then
echo "${varFLSentFileListPath}/${varFLSentFileName}... (7 Replies)
Discussion started by: Arun1992
7 Replies
LEARN ABOUT PHP
substr
SUBSTR(3) 1 SUBSTR(3)substr - Return part of a stringSYNOPSIS
string substr (string $string, int $start, [int $length])
DESCRIPTION
Returns the portion of $string specified by the $start and $length parameters.
PARAMETERS
o $string
- The input string. Must be one character or longer.
o $start
- If $start is non-negative, the returned string will start at the $start'th position in $string, counting from zero. For
instance, in the string ' abcdef', the character at position 0 is ' a', the character at position 2 is ' c', and so forth. If
$start is negative, the returned string will start at the $start'th character from the end of $string. If $string is less than or
equal to $start characters long, FALSE will be returned.
Example #1
Using a negative $start
<?php
$rest = substr("abcdef", -1); // returns "f"
$rest = substr("abcdef", -2); // returns "ef"
$rest = substr("abcdef", -3, 1); // returns "d"
?>
o $length
- If $length is given and is positive, the string returned will contain at most $length characters beginning from $start (depend-
ing on the length of $string). If $length is given and is negative, then that many characters will be omitted from the end of
$string (after the start position has been calculated when a $start is negative). If $start denotes the position of this trunca-
tion or beyond, false will be returned. If $length is given and is 0, FALSE or NULL, an empty string will be returned. If
$length is omitted, the substring starting from $start until the end of the string will be returned.
Example #2
Using a negative $length
<?php
$rest = substr("abcdef", 0, -1); // returns "abcde"
$rest = substr("abcdef", 2, -1); // returns "cde"
$rest = substr("abcdef", 4, -4); // returns false
$rest = substr("abcdef", -3, -1); // returns "de"
?>
RETURN VALUES
Returns the extracted part of $string; or FALSE on failure, or an empty string.
CHANGELOG
+--------------+---------------------------------------------------+
| Version | |
| | |
| | Description |
| | |
+--------------+---------------------------------------------------+
|5.2.2 - 5.2.6 | |
| | |
| | If the $start parameter indicates the position |
| | of a negative truncation or beyond, false is |
| | returned. Other versions get the string from |
| | start. |
| | |
+--------------+---------------------------------------------------+
EXAMPLES
Example #3
Basic substr(3) usage
<?php
echo substr('abcdef', 1); // bcdef
echo substr('abcdef', 1, 3); // bcd
echo substr('abcdef', 0, 4); // abcd
echo substr('abcdef', 0, 8); // abcdef
echo substr('abcdef', -1, 1); // f
// Accessing single characters in a string
// can also be achieved using "square brackets"
$string = 'abcdef';
echo $string[0]; // a
echo $string[3]; // d
echo $string[strlen($string)-1]; // f
?>
Example #4
substr(3) casting behaviour
<?php
class apple {
public function __toString() {
return "green";
}
}
echo "1) ".var_export(substr("pear", 0, 2), true).PHP_EOL;
echo "2) ".var_export(substr(54321, 0, 2), true).PHP_EOL;
echo "3) ".var_export(substr(new apple(), 0, 2), true).PHP_EOL;
echo "4) ".var_export(substr(true, 0, 1), true).PHP_EOL;
echo "5) ".var_export(substr(false, 0, 1), true).PHP_EOL;
echo "6) ".var_export(substr("", 0, 1), true).PHP_EOL;
echo "7) ".var_export(substr(1.2e3, 0, 4), true).PHP_EOL;
?>
The above example will output:
1) 'pe'
2) '54'
3) 'gr'
4) '1'
5) false
6) false
7) '1200'
ERRORS /EXCEPTIONS
Returns FALSE on error.
Example #5
<?php
var_dump(substr('a', 1)); // bool(false)
?>
SEE ALSO strrchr(3), substr_replace(3), preg_match(3), trim(3), mb_substr(3), wordwrap(3), String access and modification by character.
PHP Documentation Group SUBSTR(3)