I am trying to create a shell (ksh) which has two "read" commands, one which reads a line from a file and another which is inside a loop that reads user input from a keyboard. However, the "read" command inside the loop uses the input from the file and it does not get the user input from keyboard.... (3 Replies)
how do we read input from a user
e.g i want to ask a user to enter 6 sets of numbers
how do i control information from the user?
i have this.......
#!/bin/bash
echo "Please enter six numbers"
read number
echo $number >> file1
but this stops after the first number..how can i... (2 Replies)
Here is my script:
echo "var 1:"
read varone
echo "$varone"
When I run in via ksh the script runs successfully.
However when I run it via tcsh I get "varone: Undefine variable"
Does the name command not work with tcsh or do I need some additional modification? Is there a way to get... (1 Reply)
Hi everyone,
I cant seem to figure this out for the life of me. Basically, I have two arrays..
sub init {
use Getopt::Long;
use Data::Dumper;
my @selections = ();
my @valid_options = ( "vaild1", "valid2" );
GetOptions( "input=s" =>... (2 Replies)
Please tell me how to write a perl script that asks the user to enter words and that passes them to a variable.
In bash, the "read" command would achieve such user interaction.
#!/bin/bash
read -p "Enter files: " vFiles
However, I am looking for perl version of something equivalent... (2 Replies)
i have a script which takes input from user, if user gives either Y/y then it should continue, else it should quit by displaying user cancelled.
#!/bin/sh
echo " Enter your choice to continue y/Y OR n/N to quit "
read A
if
then
echo " user requested to continue "
##some commands... (7 Replies)
How to check the user input to be valid using shell script?
The valid input is in the format like as follows.
1. It can only have r,w,x or a hyphen and nothing else.
2. ensure the r, w, x are in the correct order.
for example: rwxr-xr-x is a valid format.
Thanks (5 Replies)
The (longer) script that I am working on does something like this:
#!/bin/bash
while true
do
clear
sleep 1
shuf -i1-2 -n1
sleep .1
clear
echo "Press 1 if you saw a 1. Press 2 if you saw a 2."
read -s -n1 RESPONSE
done
If the user accidentally presses two... (1 Reply)
I am trying to allow a user to enter in text and then store that text in a variable $gene to run in an awk command in which those values are used to run some calculations. I am getting syntax errors however, when I try. Thank you :).
The awk runs great if it is a pre-defined file that is used,... (7 Replies)
I'm trying to use a bash script for a psych experiment that involves listening to sound files and responding. If I have something like the code below, how can I make sure that a key press is assigned to RESPONSE only after the second echo statement?
for i in 1 2 3; do
echo "Ready?"
sleep 2
... (10 Replies)
Discussion started by: darwin_886
10 Replies
LEARN ABOUT PHP
preg_replace_callback
PREG_REPLACE_CALLBACK(3) 1 PREG_REPLACE_CALLBACK(3)preg_replace_callback - Perform a regular expression search and replace using a callbackSYNOPSIS
mixed preg_replace_callback (mixed $pattern, callable $callback, mixed $subject, [int $limit = -1], [int &$count])
DESCRIPTION
The behavior of this function is almost identical to preg_replace(3), except for the fact that instead of $replacement parameter, one
should specify a $callback.
PARAMETERS
o $pattern
- The pattern to search for. It can be either a string or an array with strings.
o $callback
- A callback that will be called and passed an array of matched elements in the $subject string. The callback should return the
replacement string. This is the callback signature:
string handler (array $matches) You'll often need the $callback function for a preg_replace_callback(3) in just one place. In
this case you can use an anonymous function to declare the callback within the call to preg_replace_callback(3). By doing it this
way you have all information for the call in one place and do not clutter the function namespace with a callback function's name
not used anywhere else.
Example #1
preg_replace_callback(3) and anonymous function
<?php
/* a unix-style command line filter to convert uppercase
* letters at the beginning of paragraphs to lowercase */
$fp = fopen("php://stdin", "r") or die("can't read stdin");
while (!feof($fp)) {
$line = fgets($fp);
$line = preg_replace_callback(
'|<p>s*w|',
function ($matches) {
return strtolower($matches[0]);
},
$line
);
echo $line;
}
fclose($fp);
?>
o $subject
- The string or an array with strings to search and replace.
o $limit
- The maximum possible replacements for each pattern in each $subject string. Defaults to -1 (no limit).
o $count
- If specified, this variable will be filled with the number of replacements done.
RETURN VALUES preg_replace_callback(3) returns an array if the $subject parameter is an array, or a string otherwise. On errors the return value is NULL
If matches are found, the new subject will be returned, otherwise $subject will be returned unchanged.
CHANGELOG
+--------+---------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------+
| 5.1.0 | |
| | |
| | The $count parameter was added |
| | |
+--------+---------------------------------+
EXAMPLES
Example #2
preg_replace_callback(3) example
<?php
// this text was used in 2002
// we want to get this up to date for 2003
$text = "April fools day is 04/01/2002
";
$text.= "Last christmas was 12/24/2001
";
// the callback function
function next_year($matches)
{
// as usual: $matches[0] is the complete match
// $matches[1] the match for the first subpattern
// enclosed in '(...)' and so on
return $matches[1].($matches[2]+1);
}
echo preg_replace_callback(
"|(d{2}/d{2}/)(d{4})|",
"next_year",
$text);
?>
The above example will output:
April fools day is 04/01/2003
Last christmas was 12/24/2002
Example #3
preg_replace_callback(3) using recursive structure to handle encapsulated BB code
<?php
$input = "plain [indent] deep [indent] deeper [/indent] deep [/indent] plain";
function parseTagsRecursive($input)
{
$regex = '#[indent]((?:[^[]|[(?!/?indent])|(?R))+)[/indent]#';
if (is_array($input)) {
$input = '<div style="margin-left: 10px">'.$input[1].'</div>';
}
return preg_replace_callback($regex, 'parseTagsRecursive', $input);
}
$output = parseTagsRecursive($input);
echo $output;
?>
SEE ALSO
PCRE Patterns, preg_quote(3), preg_replace(3), preg_last_error(3), Anonymous functions, information about the callback type.
PHP Documentation Group PREG_REPLACE_CALLBACK(3)