[SOLVED] can't use ($) dollar sign in string ... php/fi 2.0.1

Linux Chips · 07-17-2011, 08:19 AM

hi ... any one familiar with ancient php/fi 2.0.1

i have a bunch of ubnt nanostations M series (wireless access points/routers)... they use airOS (a fork of openwrt). it runs a custom firmware that i made using provided sdk. and the lighttpd uses php/fi 2.0.1.... this is (of course) used to serve the web configuration.

the problem: i need to use the ($) in a string but i couldn't. what i need to do is download some file from the internet using wget and have the pid of wget back to keep track of the process, then parse the output to the page:

Code:

$cmd = "wget $FileToDownload -O $file > $wget_log 2>&1 & echo \$!";
$pid = exec($cmd);
echo $pid;

what i get from the last echo is (\$!) not the pid. i trid removing the escape (\) then i get only (!). i also tried

Code:

"wget $FileToDownload -O $file > $wget_log 2>&1 & echo " + '$!'

then i get 36... the dot (.) operator between two string produces parse error!! e.g. "...echo ".'$!'

running the command from the terminal gives correct pid... tried manually putting the download part in a file and running it from php and it worked when i do some thing like:

Code:

$pid = exec("/tmp/download.sh")
echo $pid

but the proble with this is the same, can't write the script from php (same $ problem) and can't use a permanent one cause the file to download will change periodically

any ideas??!!

regards

kbp · 07-17-2011, 09:31 PM

How about this ? (untested)

Code:

$cmd = "wget $FileToDownload -O $file > $wget_log 2>&1";
$pidcmd = "pgrep -f wget.*$FileToDownload";
$pid = exec($pidcmd);
echo $pid;

Linux Chips · 07-18-2011, 06:28 AM

hi...
thanks for the replay

Quote:

How about this ? (untested)

Code:

$cmd = "wget $FileToDownload -O $file > $wget_log 2>&1";
$pidcmd = "pgrep -f wget.*$FileToDownload";
$pid = exec($pidcmd);
echo $pid;

do you mean?

Code:

$cmd = "wget $FileToDownload -O $file > $wget_log 2>&1";
exec($cmd);
$pidcmd = "pgrep -f wget.*$FileToDownload";
$pid = exec($pidcmd);
echo $pid;

in the first case i get a pid that is not existed!!! the second i get the correct pid plus 1 (not always), and if i try to kill that pid from the command line i get the error telling that there is no such process.

onebuck · 07-18-2011, 08:15 AM

Moved: This thread is more suitable in <Programming> and has been moved accordingly to help your thread/question get the exposure it deserves.

Linux Chips · 07-18-2011, 09:29 AM

thanks onebuck

...

well i found the problem with kbp's method (thank you, i did non know about it)... the pid returned was the one for the pgrep it self, although the man page say it dose not (weird). well it dose not return self pid from cli, only from within the php!!

i add (^) to the regex matching and it worked, now it looks like this

Code:

$cmd = "wget $FileToDownload -O $file > $wget_log 2>&1";
exec($cmd);
$pidcmd = "pgrep -f ^wget.*$FileToDownload";
$pid = exec($pidcmd);
echo $pid;

not clean as the "echo $!" thing (which works perfectly on my fedora box and php5), but it dose the trick.
still... can't i use the ($) in a string??? is it the php2 that dose not support it, or i am doing some thing wrong!!?? or may be it is the way the os is built... btw it uses busybox if that makes difference

onebuck · 07-18-2011, 09:37 AM

Hi,

Just a few links to aid you to gaining some understanding;

  1 Linux Documentation Project 
2 Rute Tutorial & Exposition 
3 Linux Command Guide  
4 Bash Beginners Guide 
5 Bash Reference Manual 
6 Advanced Bash-Scripting Guide 
7 Linux Newbie Admin Guide 
8 LinuxSelfHelp 
9 Utimate Linux Newbie Guide
10 Linux Home Networking
11 Virtualization- Top 10

The above links and others can be found at 'Slackware-Links'. More than just Slackware® links!