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Full Discussion: Help with While Loops
Top Forums UNIX for Dummies Questions & Answers Help with While Loops Post 302166764 by MaestroRage on Tuesday 12th of February 2008 06:06:38 PM
Old 02-12-2008
Help with While Loops

I am traversing down a list, and I am not quite sure how to tell the loop to break when it's done going through the file.

#!/bin/sh
while :
do
read list <&3
echo $list
done

is the code. The file "list" is simply

5
4
3
2
1

any advice on how to break the loop after the file is done reading would be great. Keep in mind the file can be of any length and no hardcoding should be advised. Thanks!
 
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break(1)                                                           User Commands                                                          break(1)

NAME
break, continue - shell built-in functions to escape from or advance within a controlling while, for, foreach, or until loop SYNOPSIS
sh break [n] continue [n] csh break continue ksh *break [n] *continue [n] DESCRIPTION
sh The break utility exits from the enclosing for or while loop, if any. If n is specified, break n levels. The continue utility resumes the next iteration of the enclosing for or while loop. If n is specified, resume at the n-th enclosing loop. csh The break utility resumes execution after the end of the nearest enclosing foreach or while loop. The remaining commands on the current line are executed. This allows multilevel breaks to be written as a list of break commands, all on one line. The continue utility continues execution of the next iteration of the nearest enclosing while or foreach loop. ksh The break utility exits from the enclosed for, while, until, or select loop, if any. If n is specified, then break n levels. If n is greater than the number of enclosing loops, the outermost enclosing loop shall be exited. The continue utility resumes the next iteration of the enclosed for, while, until, or select loop. If n is specified then resume at the n- th enclosed loop. If n is greater than the number of enclosing loops, the outermost enclosing loop shall be used. On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways: 1. Variable assignment lists preceding the command remain in effect when the command completes. 2. I/O redirections are processed after variable assignments. 3. Errors cause a script that contains them to abort. 4. Words that follow a command preceded by ** that are in the format of a variable assignment are expanded with the same rules as a vari- able assignment. This means that tilde substitution is performed after the = sign, and also that word splitting and file name genera- tion are not performed. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
csh(1), exit(1), ksh(1), sh( 1), attributes(5) SunOS 5.10 17 Jul 2002 break(1)

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