How to shorten my code? Post: 302872219

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Top Forums UNIX for Dummies Questions & Answers How to shorten my code? Post 302872219 by Scrutinizer on Friday 8th of November 2013 02:52:49 AM

11-08-2013

Moderator

Another way to do the loop, that would not involve the cut statement:

Code:

while IFS=, read _ _ _ i _
do

done < "$PAYROLL"

Quote:

Originally Posted by bakunin

[..] you should not use a "for"-loop for a possibly long list, because the expansion will let the resulting line (after evaluation of the backticks) grow and shell command lines have a certain maximum length (see the "MAX_LIN" kernel constant).

The for loop is an internal compound shell command that is part of the shell syntax and it does not suffer from these limits..

Quote:

There shall be no limit on the size of any shell command other than that imposed by the underlying system (memory constraints, {ARG_MAX}, and so on).

Shell Commands

ARG_MAX is the maximum length of arguments for a new process and that is not the case here.

Even in cases where the shell calls an external program and tries to pass too many elements, then it is not the shell that imposes this limit. It only delivers the error message...

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LEARN ABOUT OSF1

pseudo

pseudo(1)						      General Commands Manual							 pseudo(1)

NAME

       pseudo - Starts a non-STREAMS pty interface for a STREAMS device

SYNOPSIS

       pseudo [-l] [-shell shell]

OPTIONS

       Starts  a shell process as the login shell. By default, the command starts this process as an interactive shell.  Specifies the shell to be
       started.  By default, the command starts the shell set by the SHELL environment variable.

DESCRIPTION

       The pseudo command provides an appropriate interface for STREAMS tty devices that are installed on  systems  configured	to  use  the  non-
       STREAMS pty driver.

       The  pseudo  command  opens a pair of master and slave pty devices, and starts a shell process. The command's options allow you to override
       the default shell specification and to specify that the process be started as a login shell.

NOTES

       The pseudo command is available only when one or more of the Tru64 UNIX optional subsets with worldwide support software are  installed	on
       your system.

       In  order  for the pseudo command to provide a non-STREAMS pty interface for STREAMS devices, the system must be configured to use the non-
       STREAMS pty driver. If the system is configured to use the STREAMS pty driver, the command provides a STREAMS pty interface.

SEE ALSO

       Commands:  stty(1)

       Interfaces:  pty(7)

																	 pseudo(1)