Welcome as the first member of the i-shun-for-loops-for-their-inherent-danger-club. The drinks are on the clubs president - me. ;-)
You are absolutely correct and i have said it a dozen times here that for-loops on unlimited content (like a directory listing) are a dangerous thing, because the code could break as the maximum command line length is reached.
You can run it directly in a pipeline without the intermediate file:
Btw., speaking of coding practice: maybe its only me but i find it easier to read later when the input to the while-loop is at the top and not the bottom. Therefore this:
is easier to read than that, especially when the loop is long:
Hi Friends,
Can any of you explain me about the below line of code?
mn_code=`env|grep "..mn"|awk -F"=" '{print $2}'`
Im not able to understand, what exactly it is doing :confused:
Any help would be useful for me.
Lokesha (4 Replies)
Hi,
I have a problem with "for" and "while" loop in "sh".
I have:
#!/bin/sh
for i in $(seq 1 500000); do
echo $i
doneand it's working in sh on my ubuntu, but when I try to run this on unix(I have access to my university's unix) it crash:
syntax error at line 2: `$' unexpected...... (8 Replies)
Hi.
I have a copy-file script (and a move-file script) that I recently tried to make interactive. I tested the former on three files from a text list, and watched to see what would happen. As the cp command was in a while/do/done loop, there was no pause for input: it wrote the file from the... (2 Replies)
Hi,
I have line in input file as below:
3G_CENTRAL;INDONESIA_(M)_TELKOMSEL;SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL
My expected output for line in the file must be :
"1-Radon1-cMOC_deg"|"LDIndex"|"3G_CENTRAL|INDONESIA_(M)_TELKOMSEL"|LAST|"SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL"
Can someone... (7 Replies)
dear all,
i got some questions about for/while loop when working on redirect command output to for/while loop.
take one for example :
in for loop :
allfiles=`find /var/log -maxdepth 1 -type f -mtime +5`
index=1
for ((i=0; i<${#allfiles}; i++)); do
echo "$index:${allfiles}"
... (2 Replies)
How to use "mailx" command to do e-mail reading the input file containing email address, where column 1 has name and column 2 containing “To” e-mail address
and column 3 contains “cc” e-mail address to include with same email.
Sample input file, email.txt
Below is an sample code where... (2 Replies)
Hi everybody,
I am new at Unix/Bourne shell scripting and with my youngest experiences, I will not become very old with it :o
My code:
#!/bin/sh
set -e
set -u
export IFS=
optl="Optl"
LOCSTORCLI="/opt/lsi/storcli/storcli"
($LOCSTORCLI /c0 /vall show | grep RAID | cut -d " "... (5 Replies)
Hello.
System : opensuse leap 42.3
I have a bash script that build a text file.
I would like the last command doing :
print_cmd -o page-left=43 -o page-right=22 -o page-top=28 -o page-bottom=43 -o font=LatinModernMono12:regular:9 some_file.txt
where :
print_cmd ::= some printing... (1 Reply)
Hi 2 all,
i have had AIX 7.2
:/# /usr/IBMAHS/bin/apachectl -v
Server version: Apache/2.4.12 (Unix)
Server built: May 25 2015 04:58:27
:/#:/# /usr/IBMAHS/bin/apachectl -M
Loaded Modules:
core_module (static)
so_module (static)
http_module (static)
mpm_worker_module (static)
... (3 Replies)
Discussion started by: penchev
3 Replies
LEARN ABOUT DEBIAN
io::async::test
IO::Async::Test(3pm) User Contributed Perl Documentation IO::Async::Test(3pm)NAME
"IO::Async::Test" - utility functions for use in test scripts
SYNOPSIS
use Test::More tests => 1;
use IO::Async::Test;
use IO::Async::Loop;
my $loop = IO::Async::Loop->new;
testing_loop( $loop );
my $result;
$loop->do_something(
some => args,
on_done => sub {
$result = the_outcome;
}
);
wait_for { defined $result };
is( $result, what_we_expected, 'The event happened' );
...
my $buffer = "";
my $handle = IO::Handle-> ...
wait_for_stream { length $buffer >= 10 } $handle => $buffer;
is( substr( $buffer, 0, 10, "" ), "0123456789", 'Buffer was correct' );
DESCRIPTION
This module provides utility functions that may be useful when writing test scripts for code which uses "IO::Async" (as well as being used
in the "IO::Async" test scripts themselves).
Test scripts are often synchronous by nature; they are a linear sequence of actions to perform, interspersed with assertions which check
for given conditions. This goes against the very nature of "IO::Async" which, being an asynchronisation framework, does not provide a
linear stepped way of working.
In order to write a test, the "wait_for" function provides a way of synchronising the code, so that a given condition is known to hold,
which would typically signify that some event has occured, the outcome of which can now be tested using the usual testing primitives.
Because the primary purpose of "IO::Async" is to provide IO operations on filehandles, a great many tests will likely be based around
connected pipes or socket handles. The "wait_for_stream" function provides a convenient way to wait for some content to be written through
such a connected stream.
FUNCTIONS
testing_loop( $loop )
Set the "IO::Async::Loop" object which the "wait_for" function will loop on.
wait_for( $condfunc )
Repeatedly call the "loop_once" method on the underlying loop (given to the "testing_loop" function), until the given condition function
callback returns true.
To guard against stalled scripts, if the loop indicates a timeout for 10 consequentive seconds, then an error is thrown.
wait_for_stream( $condfunc, $handle, $buffer )
As "wait_for", but will also watch the given IO handle for readability, and whenever it is readable will read bytes in from it into the
given buffer. The buffer is NOT initialised when the function is entered, in case data remains from a previous call.
$buffer can also be a CODE reference, in which case it will be invoked being passed data read from the handle, whenever it is readable.
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.14.2 2012-10-24 IO::Async::Test(3pm)