Sponsored Content
Top Forums Shell Programming and Scripting piping and backgroud processes (daemons) Post 302207246 by quine on Thursday 19th of June 2008 12:24:44 PM
Old 06-19-2008
What you are looking for is to set $| = 1; on the currently selected file handle (by default STDOUT). $| also known as $OUTPUT_AUTOFLUSH and also $AUTOFLUSH turns OFF buffering when set and so you will see the results of every print as it happens instead of when perl figures it's time to flush the output buffer. Buffering is ON in perl by default. If you are printing to STDOUT you have only to do a $| = 1; somewhere before your while loop. If you print to some other handle be sure to select(HANDLE); before you assign to $|, etc.
 

9 More Discussions You Might Find Interesting

1. IP Networking

DNS daemons

Does anyone know the command to start the DNS Daemon. I looked in the /etc/init.d/inetsvc file and it tells me what the text should look like. When I go to open the corresponding files they are encoded and I can't read them. So is there a command that will start the DNS daemon? If... (8 Replies)
Discussion started by: Deuce
8 Replies

2. UNIX for Advanced & Expert Users

backgroud process

Hi experts How to write a shell program(sh) that running on the backgroud when foreground processing something, such as prompt ....... till the background process finished. thx (4 Replies)
Discussion started by: trynew
4 Replies

3. UNIX for Dummies Questions & Answers

Daemons

MYSQL-daemon don't started automatically by system-start. And same trouble with httpd too. I have SuSE 8.0. What can I do ? Thanks.... (6 Replies)
Discussion started by: Pennywize
6 Replies

4. Linux

A doubt on Daemons

Hi there! I'm a bit curious on something about Daemons.... Supose you have two processes say A and B, where B is a daemon. A is totally independent from B. Is there a way for A to find out B's return code? Is there a way for A to find out when B ends? Thanks! (4 Replies)
Discussion started by: marioh
4 Replies

5. UNIX for Dummies Questions & Answers

Starting daemons at reboot.

I rebooted my server (solaris 5.8) and I had to manually start the cron and mailx daemons. How do I get these to automatically start at reboot? Thanks in advance. (2 Replies)
Discussion started by: shorty
2 Replies

6. Shell Programming and Scripting

daemons definition

hi there, can somebody give me a definition for daemons, or example what are they !! and what the use for? i've done some research and all what i found is /etc/... or /usr/bin/... and i haven't quietly got the concept. any ideas !! Thanks. (5 Replies)
Discussion started by: new2Linux
5 Replies

7. Shell Programming and Scripting

multiple child scripts running in backgroud, how to use grep on the parent?

Hi I have a shell script A which calls another 10 shell scripts which run in background. How do i make the parent script wait for the child scripts complete, or in other words, i must be able to do a grep of parent script to find out if the child scripts are still running. My Code: ... (5 Replies)
Discussion started by: albertashish
5 Replies

8. HP-UX

status of daemons

Hi there all, Hey, is there a way to get the status of all daemons running on a HPUX? in an easy way? Like the same way how to vieuw the status of packages in cmviewcl. Thanks! (1 Reply)
Discussion started by: draco
1 Replies

9. Shell Programming and Scripting

Running commands in backgroud

I have a small question may be this will be discussed before I have two files file1 and file2 with huge data and I am running the commands as cat file1 |sort & cat file2 |sort & If the session is got disconnected or logout will this command run in background, or shall we use nohup (3 Replies)
Discussion started by: morbid_angel
3 Replies
Symbol(3pm)						 Perl Programmers Reference Guide					       Symbol(3pm)

NAME
Symbol - manipulate Perl symbols and their names SYNOPSIS
use Symbol; $sym = gensym; open($sym, "filename"); $_ = <$sym>; # etc. ungensym $sym; # no effect # replace *FOO{IO} handle but not $FOO, %FOO, etc. *FOO = geniosym; print qualify("x"), " "; # "main::x" print qualify("x", "FOO"), " "; # "FOO::x" print qualify("BAR::x"), " "; # "BAR::x" print qualify("BAR::x", "FOO"), " "; # "BAR::x" print qualify("STDOUT", "FOO"), " "; # "main::STDOUT" (global) print qualify(*x), " "; # returns *x print qualify(*x, "FOO"), " "; # returns *x use strict refs; print { qualify_to_ref $fh } "foo! "; $ref = qualify_to_ref $name, $pkg; use Symbol qw(delete_package); delete_package('Foo::Bar'); print "deleted " unless exists $Foo::{'Bar::'}; DESCRIPTION
"Symbol::gensym" creates an anonymous glob and returns a reference to it. Such a glob reference can be used as a file or directory handle. For backward compatibility with older implementations that didn't support anonymous globs, "Symbol::ungensym" is also provided. But it doesn't do anything. "Symbol::geniosym" creates an anonymous IO handle. This can be assigned into an existing glob without affecting the non-IO portions of the glob. "Symbol::qualify" turns unqualified symbol names into qualified variable names (e.g. "myvar" -> "MyPackage::myvar"). If it is given a second parameter, "qualify" uses it as the default package; otherwise, it uses the package of its caller. Regardless, global variable names (e.g. "STDOUT", "ENV", "SIG") are always qualified with "main::". Qualification applies only to symbol names (strings). References are left unchanged under the assumption that they are glob references, which are qualified by their nature. "Symbol::qualify_to_ref" is just like "Symbol::qualify" except that it returns a glob ref rather than a symbol name, so you can use the result even if "use strict 'refs'" is in effect. "Symbol::delete_package" wipes out a whole package namespace. Note this routine is not exported by default--you may want to import it explicitly. BUGS
"Symbol::delete_package" is a bit too powerful. It undefines every symbol that lives in the specified package. Since perl, for performance reasons, does not perform a symbol table lookup each time a function is called or a global variable is accessed, some code that has already been loaded and that makes use of symbols in package "Foo" may stop working after you delete "Foo", even if you reload the "Foo" module afterwards. perl v5.16.2 2012-08-26 Symbol(3pm)
All times are GMT -4. The time now is 05:24 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy