I am trying to write to a serial port and capture the reponse in a file -
Code:
adduser ethan dialout
The user `ethan' is already a member of `dialout'
root@meow:/home/ethan# ls -l /dev/ttyS0
crw-rw-r-- 1 ethan dialout 4, 64 Oct 7 20:55 /dev/ttyS0
$fh1 = fopen("/dev/ttyS0", "w+");
fwrite($fh1, "W\n"); //This sends a signal to a scale to return the weight of an object
fread($fh1, 100);
echo $fh1;
If I run this code -
Warning: fopen(/dev/ttyS0): failed to open stream: Permission denied in /var/www/TestScale.php on line 20
Warning: fwrite() expects parameter 1 to be resource, boolean given in /var/www/TestScale.php on line 21
Warning: fread() expects parameter 1 to be resource, boolean given in /var/www/TestScale.php on line 22
I think my serial port(on board) is not working ......
because when I am running same code on two machines its working good....but when my system comes into picture ....it doesnt show any output comming from serial port..........
can anybody tell me how to configure my serial port.........or to... (16 Replies)
Hi,
I am working with solaris 9,SUN-Blade-100 and I want to communicate with the Serial port.To check whether the port is working or not.I write code and when I execute the file,then I got the output--
According to this,serial port is not found.can anyone please tell me how to configure the... (1 Reply)
I have a need to determine when a string has been completely sent via a serial port from a standard 'C' application. The code is as follows:
SerialPort_Send = open (pPortString, O_WRONLY | O_NOCTTY | O_NONBLOCK);
write (SerialPort_Send, pCommandString, strlen (pCommandString));
... (2 Replies)
Hi,
How can i configure my modem in AIX thru serial port (sa0-->tty0)
I have two port serial card configured as sa0
I created tty1 which port is tty0 and which port is tty1 how can i know?? (1 Reply)
A neighbour's Ubuntu 10.04 machine has five serial ports, one on the motherboard and four on a PCI card. However, only four cards are showing:
# dmesg | grep tty
console enabled
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:08: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
... (2 Replies)
Hi,
I have a external board connected to my serial port. I need to execute "shutdown -r now" command when system boot up. When system boots up it requires a username ans password. Then I need to run my command. I can use rc script but that is rebooting system before it asks for username and... (0 Replies)
Hi Everyone,
In my environment, I have few T5220. On the iLOM Management Card, I have both Network and Serial port are cabled, I don't have any issues while I try to connect using Network Management port, but when I try to connect the serial port for the same server which is actually connected... (3 Replies)
hello all,
please any one can provide me the shell script to write data to /dev/ttyS1
and read responce from /dev/ttyS1 and compare the responce to some string ..
thnxx
---------- Post updated at 03:35 PM ---------- Previous update was at 11:46 AM ----------
any body help me..
how do i... (1 Reply)
Hello,
I have an unloaded T5140 machine and want to access the ILOM for the first time and subsequently the network port after that., and then load Solaris 10 the final January 2011 build.
The first part is what confuses me -the cabling.
I am coming from a Windows machine (w/appropriate... (5 Replies)
Discussion started by: joboy
5 Replies
LEARN ABOUT PHP
fread
FREAD(3) 1 FREAD(3)fread - Binary-safe file readSYNOPSIS
string fread (resource $handle, int $length)
DESCRIPTION fread(3) reads up to $length bytes from the file pointer referenced by $handle. Reading stops as soon as one of the following conditions is
met:
o$length bytes have been read
o EOF (end of file) is reached
o a packet becomes available or the socket timeout occurs (for network streams)
o if the stream is read buffered and it does not represent a plain file, at most one read of up to a number of bytes equal to the
chunk size (usually 8192) is made; depending on the previously buffered data, the size of the returned data may be larger than the
chunk size.
PARAMETERS
o $handle
-A file system pointer resource that is typically created using fopen(3).
o $length
- Up to $length number of bytes read.
RETURN VALUES
Returns the read string or FALSE on failure.
EXAMPLES
Example #1
A simple fread(3) example
<?php
// get contents of a file into a string
$filename = "/usr/local/something.txt";
$handle = fopen($filename, "r");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>
Example #2
Binary fread(3) example
Warning
On systems which differentiate between binary and text files (i.e. Windows) the file must be opened with 'b' included in
fopen(3) mode parameter.
<?php
$filename = "c:\files\somepic.gif";
$handle = fopen($filename, "rb");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>
Example #3
Remote fread(3) examples
Warning
When reading from anything that is not a regular local file, such as streams returned when reading remote files or from
popen(3) and fsockopen(3), reading will stop after a packet is available. This means that you should collect the data
together in chunks as shown in the examples below.
<?php
// For PHP 5 and up
$handle = fopen("http://www.example.com/", "rb");
$contents = stream_get_contents($handle);
fclose($handle);
?>
<?php
$handle = fopen("http://www.example.com/", "rb");
if (FALSE === $handle) {
exit("Failed to open stream to URL");
}
$contents = '';
while (!feof($handle)) {
$contents .= fread($handle, 8192);
}
fclose($handle);
?>
NOTES
Note
If you just want to get the contents of a file into a string, use file_get_contents(3) as it has much better performance than the
code above.
Note
Note that fread(3) reads from the current position of the file pointer. Use ftell(3) to find the current position of the pointer
and rewind(3) to rewind the pointer position.
SEE ALSO fwrite(3), fopen(3), fsockopen(3), popen(3), fgets(3), fgetss(3), fscanf(3), file(3), fpassthru(3), ftell(3), rewind(3).
PHP Documentation Group FREAD(3)