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Full Discussion: Increase the buffer size to read lengthy lines
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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LEARN ABOUT HPUX

acctcon2

acctcon(1M)															       acctcon(1M)

NAME

       acctcon, acctcon1, acctcon2 - connect-time accounting

SYNOPSIS

       [options]

       [options]

DESCRIPTION

       The  command converts a sequence of login/logoff records read from its standard input to a sequence of records, one per login session.  Its
       input should normally be redirected from or Its output is ASCII, giving device, user ID, login name, prime  connect  time  (seconds),  non-
       prime  connect  time  (seconds), session starting time (numeric), and starting date and time.  Prime connect time is defined as the connect
       time within a specific prime period on a non-holiday weekday (Monday through Friday).  The starting and ending time of the prime period and
       the year's holidays are defined in file

       expects as input a sequence of login session records, produced by and converts them into total accounting records (see format in acct(4)).

       combines the functionality of and into one program.  It takes the same input format as and writes the same output as

       recognizes the following options:

	      Print input only, showing line name, login name,
			     and time (in both numeric and date/time formats).

	      maintains a list of lines on which users are logged in.
			     When  it  reaches	the end of its input, it emits a session record for each line that still appears to be active.	It
			     normally assumes that its input is a current file, so that it uses the current time as the ending time for each  ses-
			     sion  still in progress.  The flag causes it to use, instead, the last time found in its input, thus ensuring reason-
			     able and repeatable numbers for non-current files.

       and recognize the following options:

	      file	     is created to contain a summary of line usage showing line name, number of minutes used, percentage of total  elapsed
			     time  used,  number  of sessions charged, number of logins, and number of logoffs.  This file helps track line usage,
			     identify bad lines, and find software and hardware oddities.  Hang-up, termination of (see login(1)), and termination
			     of  the login shell each generate logoff records, so that the number of logoffs is often three to four times the num-
			     ber of sessions.  See init(1M) and utmp(4).

	      file	     is filled with an overall record for the accounting period, giving starting time, ending time, number of reboots, and
			     number of date changes.

	      When this option is used, the records of the type found in
			     are read from the specified input.

EXAMPLES

       These  commands	are  typically	used as shown below.  The file is created only for the use of commands described by the acctprc(1M) manual
       entry:

       or

       With option:

       or

Note:
       The file can be either or a file containing records of the type found in

WARNINGS

       The line usage report is confused by date changes.  Use (see fwtmp(1M)) to correct this situation.

FILES

SEE ALSO

       login(1), acct(1M), acctcms(1M), acctcom(1M), acctmerg(1M), acctprc(1M), acctsh(1M), fwtmp(1M), init(1M), utmpd(1M), runacct(1M),  acct(2),
       getbwent(3C), acct(4), utmp(4).

STANDARDS CONFORMANCE

																       acctcon(1M)
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