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Top Forums Shell Programming and Scripting Increase the buffer size to read lengthy lines Post 302175985 by era on Monday 17th of March 2008 04:03:41 AM
Old 03-17-2008
Your problem is not "buffer size". If you are using a command which reads one line at a time, it will read even long lines, but if the input is more than one line, it will only read the first line.

Let's rephrase this problem. How do you know when something is more than one line? Because the next line is then not a date stamp. So you can create a simple parser for this format, which recognizes everything up to the next date stamp as one input record.

This is probably best done with a scripting language such as awk or Perl or Python, but just for the sake of argument, here's a quick and dirty solution in shell script:

Code:
#!/bin/sh

date=
input=
nl="
"  # yes, that's opening quote, newline, closing quote
while read line; do
  case $line in
    *day\ [0-9][0-9]\ *\ [12][0-9][0-9][0-9]\ *)
      # warning! y3k problem
      # warning! fragile matching, would be better with regex
      # warning! basically untested code anyway
      case $date in '') ;;
        *) echo "Result for '$date'":
	    echo "$input" ;;
      esac
      input=
      date=$line
      ;;
    *)
      input="$input${input:+$nl}$line"
      ;;
  esac
done

# whatever is left at end of file is a result too
echo "Result for '$date'":
echo "$input"

era
 

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DATETIME.__CONSTRUCT(3) 						 1						   DATETIME.__CONSTRUCT(3)

DateTime::__construct - Returns new DateTime object

       Object oriented style

SYNOPSIS
public DateTime::__construct NULL ([string $time = "now"], [DateTimeZone $timezone]) DESCRIPTION
Procedural style DateTime date_create NULL ([string $time = "now"], [DateTimeZone $timezone]) Returns new DateTime object. PARAMETERS
o $time -A date/time string. Valid formats are explained in Date and Time Formats. Enter NULL here to obtain the current time when using the $timezone parameter. o $timezone - A DateTimeZone object representing the timezone of $time. If $timezone is omitted, the current timezone will be used. Note The $timezone parameter and the current timezone are ignored when the $time parameter either is a UNIX timestamp (e.g. @946684800) or specifies a timezone (e.g. 2010-01-28T15:00:00+02:00). RETURN VALUES
Returns a new DateTime instance. Procedural style returns FALSE on failure. ERRORS
/EXCEPTIONS Emits Exception in case of an error. CHANGELOG
+--------+---------------------------------------------------+ |Version | | | | | | | Description | | | | +--------+---------------------------------------------------+ | 5.3.0 | | | | | | | If $time contains an invalid date/time format, | | | then an exception is now thrown. Previously an | | | error was emitted. | | | | +--------+---------------------------------------------------+ EXAMPLES
Example #1 DateTime.__construct(3) example Object oriented style <?php try { $date = new DateTime('2000-01-01'); } catch (Exception $e) { echo $e->getMessage(); exit(1); } echo $date->format('Y-m-d'); ?> Procedural style <?php $date = date_create('2000-01-01'); if (!$date) { $e = date_get_last_errors(); foreach ($e['errors'] as $error) { echo "$error "; } exit(1); } echo date_format($date, 'Y-m-d'); ?> The above examples will output: 2000-01-01 Example #2 Intricacies of DateTime.__construct(3) <?php // Specified date/time in your computer's time zone. $date = new DateTime('2000-01-01'); echo $date->format('Y-m-d H:i:sP') . " "; // Specified date/time in the specified time zone. $date = new DateTime('2000-01-01', new DateTimeZone('Pacific/Nauru')); echo $date->format('Y-m-d H:i:sP') . " "; // Current date/time in your computer's time zone. $date = new DateTime(); echo $date->format('Y-m-d H:i:sP') . " "; // Current date/time in the specified time zone. $date = new DateTime(null, new DateTimeZone('Pacific/Nauru')); echo $date->format('Y-m-d H:i:sP') . " "; // Using a UNIX timestamp. Notice the result is in the UTC time zone. $date = new DateTime('@946684800'); echo $date->format('Y-m-d H:i:sP') . " "; // Non-existent values roll over. $date = new DateTime('2000-02-30'); echo $date->format('Y-m-d H:i:sP') . " "; ?> The above example will output something similar to: 2000-01-01 00:00:00-05:00 2000-01-01 00:00:00+12:00 2010-04-24 10:24:16-04:00 2010-04-25 02:24:16+12:00 2000-01-01 00:00:00+00:00 2000-03-01 00:00:00-05:00 SEE ALSO
DateTime.createFromFormat(3), DateTimeZone.__construct(3), Date and Time Formats, date.timezone ini setting, date_default_time- zone_set(3), DateTime.getLastErrors(3), checkdate(3). PHP Documentation Group DATETIME.__CONSTRUCT(3)
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