awk doesn't understand 'read' statement!!! Post: 302796793

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Top Forums Shell Programming and Scripting awk doesn't understand 'read' statement!!! Post 302796793 by Don Cragun on Saturday 20th of April 2013 08:00:51 PM

04-20-2013

Registered User

Quote:

Originally Posted by hanson44

Yes, alister is right. "read" is very different from "break" and "continue".

Also, awk is very different from shell. One huge difference is that awk is not intended as an interactive environment.

There is no reason why awk can't be used interactively. If you don't specify any input file for your awk program, it will read from standard input. If you need your awk program to read initialization data from a file and then interact with a user by reading standard input after that, use the name of the initialization data file as the first file operand and - as the next file operand.

When I'm testing small awk programs to see why some expression isn't working the way I expected, I frequently type in a small awk program and then just type input into it see what happens (and end it with ctl-D).

It is true that the shell and awk languages are different, but awk certainly has multiple ways to read and write files. Look at the awk man page on your system and search for the descriptions of functions like close, getline, print, printf, and system.

And as several people have said, break and continue have nothing to do with reading a file; they are used inside while and for loops for flow control in those loops.

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LEARN ABOUT DEBIAN

tzselect

TZSELECT(8)						    Linux System Administration 					       TZSELECT(8)

NAME

       tzselect - select a timezone

SYNOPSIS

       tzselect

DESCRIPTION

       The  tzselect  program asks the user for information about the current location, and outputs the resulting timezone description to standard
       output.	The output is suitable as a value for the TZ environment variable.

       All interaction with the user is done via standard input and standard error.

EXIT STATUS

       The exit status is zero if a timezone was successfully obtained from the user, nonzero otherwise.

ENVIRONMENT

       AWK    Name of a Posix-compliant awk program (default: awk).

       TZDIR  Name of the directory containing timezone data files (default: /usr/share/zoneinfo).

FILES

       TZDIR/iso3166.tab
	      Table of ISO 3166 2-letter country codes and country names.

       TZDIR/zone.tab
	      Table of country codes, latitude and longitude, TZ values, and descriptive comments.

       TZDIR/TZ
	      Time zone data file for timezone TZ.

SEE ALSO

       tzfile(5), zdump(8), zic(8)

COLOPHON

       This page is part of release 3.44 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

								    2007-05-18							       TZSELECT(8)