Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: My for loop decides to become an infinite loop?
Top Forums Shell Programming and Scripting My for loop decides to become an infinite loop? Post 302580703 by Corona688 on Friday 9th of December 2011 10:22:49 AM
Old 12-09-2011
Quote:
Originally Posted by gotreef
It looks like your little script snippit solved all my problems plus I feel like I've learned a lot as well, for which I'm greatful.

One quick thing though. When you have the "while read FILE", how does it know that the FILE is the /tmp/$$ file?
Glad it worked for you.

It doesn't -- it just reads from standard input. But the </tmp/$$ tells it what "standard input" is supposed to be, at the bottom of the loop.

Imagine it like this:
Code:
read FILE </tmp/$$

...except that there's an entire loop involved:
Code:
while read FILE
do
...
done </tmp/$$

...in which the file gets opened once and put into standard input for read and anything else inside the loop to read as it pleases.

You can do that, in shell -- redirect the input and/or output of entire loops and statements:

Code:
# all 5 echo statements go into the same file
for N in 1 2 3 4 5
do
        echo $N
done > output

 

10 More Discussions You Might Find Interesting

1. Solaris

ls command in infinite Loop

Hi, whenever I am giving a 'ls' command system is going into infinite loop displaying the current home directory. There is no separate shell script/file with ls name anywhere in the system. I am using Solaris 10. Any help / guidance in solving this problem is highly appreciated. ... (3 Replies)
Discussion started by: umakant
3 Replies

2. Shell Programming and Scripting

Infinite loop not looping

Hi guys, I'm having a problem getting my infinite loop to loop. It simply reads in the users choice form the menu, executes the corresponding case statement and quits instead of looping back to the main menu again. I have a feeling it might be something with my if then statements within the case... (2 Replies)
Discussion started by: hootdocta5
2 Replies

3. Programming

Is my code in an Infinite Loop?

Production C code compiled without the dash-g option is running, and seems to be in an infinite loop. Is there a way to tell? Is there a diagnostic tool that will report what objects or what lines of code or even what functions are being executed? Or is my best option to kill it with a dump? ... (5 Replies)
Discussion started by: marcus121
5 Replies

4. Shell Programming and Scripting

infinite while do loop problem

hi all, this is how my scrip looks like #!/bin/sh bindir='/opt/apps/script/bin' datadir='/opt/apps/script/data' dir='/opt/apps/script' while : ; do ls -1rt /opt/apps/script/data/check.txt*|tail -1 > /dev/null 2>&1 if ;then chmod +rwx $bindir/dummy2.sh ... (8 Replies)
Discussion started by: tententen
8 Replies

5. Shell Programming and Scripting

Infinite while loop

what is the difference between while:,while true and while false? (6 Replies)
Discussion started by: proactiveaditya
6 Replies

6. UNIX for Advanced & Expert Users

Procmail and infinite loop

I wanted to copy (not forward but copy) all incoming email to another address of mine. It worked, but now I encountered an infinite loop problem: When the second address doesn't like the content and bounces the message back, the bounce message will be sent back and forth. So, what I have in... (1 Reply)
Discussion started by: distill
1 Replies

7. Shell Programming and Scripting

Call a infinite loop

Hi All, I need to run an infinite loop. requirement below: function1 --> creates a file file1 function2 ---> need to call if the file creates i am running these both function via a script --> script.sh i need to run the function1 first and if the file file1 creates then need to run the... (3 Replies)
Discussion started by: satyaranjon
3 Replies

8. Homework & Coursework Questions

Help with infinite loop problem

1. The problem statement, all variables and given/known data: My problem is an infinite loop when i press any other key other then Y or y in the while loop. what i want it to do is return to the normal script outside of it if pressing N or n or keep asking the same question if its any other... (4 Replies)
Discussion started by: Ren_kun
4 Replies

9. Shell Programming and Scripting

How to stop infinite loop

Im unable to stop the below infinite loop (bash script). Can someone tell me why this isnt responding to signals eg: ctrl+c (SIGINT) or ctrl+z c=0 test_loop() { c=$(($c+1)) echo "count value is : $c " sleep 1 test_loop } Im using: SunOS 5.10 PS: If run this as... (13 Replies)
Discussion started by: Arun_Linux
13 Replies

10. Shell Programming and Scripting

Infinite loop query

I have a script script.shwhich is scheduled to run at 11 AM everyday. # script.sh Code: ./scb_script.sh & unfortunately scb_script.sh is running today in infinite loop as respective files are not available. My question, when script.sh starts running tomorrow, will the old process be... (1 Reply)
Discussion started by: JSKOBS
1 Replies

LEARN ABOUT XFREE86

apple_dump

APPLE_DUMP(1)							   Netatalk 2.2 						     APPLE_DUMP(1)

NAME

       apple_dump - Dump AppleSingle/AppleDouble format file

SYNOPSIS

       apple_dump [-a] FILE | DIR
							  apple_dump -f FILE
							  apple_dump -d FILE
							  apple_dump -h | -help | --help
							  apple_dump -v | -version | --version

DESCRIPTION

       apple_dump dump AppleSingle/AppleDouble format file.

OPTIONS

       -a FILE|DIR
	   This is default. Dump a AppleSingle/AppleDouble file for FILE or DIR automatically. Extrapolate FinderInfo type from absolute path. If
	   FILE is not AppleSingle/AppleDouble format, look for .AppleDouble/FILE and ._FILE. If DIR, look for DIR/.AppleDouble/.Parent and ._DIR.

       -f FILE
	   Dump FILE. Assume FinderInfo to be FileInfo.

       -d FILE
	   Dump FILE. Assume FinderInfo to be DirInfo.

       -h, -help, --help
	   Display the help and exit

       -v, -version, --version
	   Show version and exit

NOTE

       There is no way to detect whether FinderInfo is FileInfo or DirInfo. By default, apple_dump examins whether file or directory, a parent
       directory is .AppleDouble, filename is ._*, filename is .Parent, and so on.

       If setting option -f or -d, assume FinderInfo and doesn't look for another file.

SEE ALSO

       ad(1)

Netatalk 2.2							    02 Sep 2011 						     APPLE_DUMP(1)
All times are GMT -4. The time now is 04:44 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy