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...

Scrutinizer

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LEARN ABOUT NETBSD

tput

TPUT(1) 						    BSD General Commands Manual 						   TPUT(1)

NAME

     tput, clear -- terminal capability interface

SYNOPSIS

     tput [-T term] attribute [attribute-args] ...

DESCRIPTION

     tput makes terminal-dependent information available to users or shell applications.  The options are as follows:

     -T      The terminal name as specified in the terminfo(5) database, for example, ``vt100'' or ``xterm''.  If not specified, tput retrieves
	     the ``TERM'' variable from the environment.

     tput outputs a string if the attribute is of type string; a number if it is of type integer.  Otherwise, tput exits 0 if the terminal has the
     capability and 1 if it does not, without further action.

     If the attribute is of type string, and takes arguments (e.g. cursor movement, the terminfo ``cup'' sequence) the arguments are taken from
     the command line immediately following the attribute.

     The following special attributes are available:

     clear	   Clear the screen (the terminfo(5) ``cl'' sequence).

     init	   Initialize the terminal (the terminfo(5) ``is2'' sequence).

     longname	   Print the descriptive name of the user's terminal type.

     reset	   Reset the terminal (the terminfo(5) ``rs1, rs2, rs3'' and ``rf'' sequence).

EXIT STATUS

     The exit status of tput is based on the last attribute specified.	If the attribute is of type string or of type integer, tput exits 0 if the
     attribute is defined for this terminal type and 1 if it is not.  If the attribute is of type boolean, tput exits 0 if the terminal has this
     attribute, and 1 if it does not.  tput exits 2 if any error occurred.

EXAMPLES

     tput cl cm 5 10	clear the screen and goto line 5 column 10

     tput cm 6 11 DC 6	goto line 6 column 11 and delete 6 characters

SEE ALSO

     termcap(3), termcap(5)

HISTORY

     The tput command appears in 4.4BSD.

BUGS

     tput can't really distinguish between different types of attributes.

     Not all terminfo entries contain the reset sequence, so using the init sequence may be more useful.

BSD
								September 29, 2009							       BSD