Is your script supposed to be invoked with the files you want to process, and terminate if they don't exist? $# indicates how many arguments there were (presumably you want to abort if there were none) but to check whether the named file(s) exist, you give them as arguments to "test -f".
Hi,
I would like to perform bash which would check the file A.txt to be size 0 or not. If the size is 0, I would copy file B.txt to replace A.txt.
Please help.
Thanks.
-Jason (6 Replies)
I have a process run weekly where I must convert data formats for about thirty files. I read a text file that provides all of the filenames and switch settings.
My perl code is:
for ($j = 1; $j <= $k; $j++)
{
open(FIN2,$fin2) || die "open: $!";
do other stuff
}
Every once in... (2 Replies)
In a directory a number of files named res0.om res1.om ... resN.om
where N can be any unknown number between 1 and 999
Please help me filling out the gaps in the following csh script:
I need to delete all files exept res0.om The easy way is
rm res1*
rm res2*
rm res3*
rm res4*... (5 Replies)
I have the following data stored in a file.
1 /home/file13 /home/file2
2 /home/file41 /home/file654
3 /home/file61 /home/file45
4 /home/file81 /home/file43
...
I want to print the first column provided the files represented by the second and third column exist.
How to do that? (3 Replies)
Hi,
I am new to shell-scripting, and doing a lot of reading. I am having some trouble getting started with a simple testing of scripting. I have been experimenting with if, loops, for, test, etc., but still unsure. I seem to have the hang of it when it comes to creating a single file or... (6 Replies)
I have a setup where I have two drives.
TV
TVbackup
For what ever reason, I have a lot of content on my TVbackup drive which isn't on my TV drive.
I want to copy all the files across which are on TVbackup but are not currently on TV.
If there is a file with the same name but a... (2 Replies)
Hi all!
I need some help with a script, but I want to make it better, my script prints the last two files on each directory:
echo " "
echo "******************* mediation_sgsn:***********************"
ls -lrt /moneta_collected03/mediation_sgsn | tail -2
echo " "
echo... (6 Replies)
Hi,
I am unable to achieve the file exist conditions if there are multiple files same similar name for e.g. in a $Direct i am having files like
aus.txt
aus.txt_pr
aus.txt_2012
i need to put a file exist condition like which is not working
then
echo "File present"
but the... (9 Replies)
I want to run find and wondering if it struggles when there are many files. I have tried
and does not seem to complain.
Is this correct? (8 Replies)
Discussion started by: kristinu
8 Replies
LEARN ABOUT PHP
popen
POPEN(3) 1 POPEN(3)popen - Opens process file pointerSYNOPSIS
resource popen (string $command, string $mode)
DESCRIPTION
Opens a pipe to a process executed by forking the command given by $command.
PARAMETERS
o $command
- The command
o $mode
- The mode
RETURN VALUES
Returns a file pointer identical to that returned by fopen(3), except that it is unidirectional (may only be used for reading or writing)
and must be closed with pclose(3). This pointer may be used with fgets(3), fgetss(3), and fwrite(3). When the mode is 'r', the returned
file pointer equals to the STDOUT of the command, when the mode is 'w', the returned file pointer equals to the STDIN of the command.
If an error occurs, returns FALSE.
EXAMPLES
Example #1
popen(3) example
<?php
$handle = popen("/bin/ls", "r");
?>
If the command to be executed could not be found, a valid resource is returned. This may seem odd, but makes sense; it allows you to
access any error message returned by the shell:
Example #2
popen(3) example
<?php
error_reporting(E_ALL);
/* Add redirection so we can get stderr. */
$handle = popen('/path/to/executable 2>&1', 'r');
echo "'$handle'; " . gettype($handle) . "
";
$read = fread($handle, 2096);
echo $read;
pclose($handle);
?>
NOTES
Note
If you're looking for bi-directional support (two-way), use proc_open(3).
Note
When safe mode is enabled, you can only execute files within the safe_mode_exec_dir. For practical reasons, it is currently not
allowed to have .. components in the path to the executable.
Warning
With safe mode enabled, the command string is escaped with escapeshellcmd(3). Thus, echo y | echo x becomes echo y | echo x.
SEE ALSO pclose(3), fopen(3), proc_open(3).
PHP Documentation Group POPEN(3)