Hi,
I was wondering why ls * | echo does not print the contents of the directory to the screen? The way I see it, ls * returns a whole lot of information, and then we pipe all this info to echo, so surely it should all come to our screen!
Is there a serious flaw in my understanding?
... (3 Replies)
Not sure why this does not work in bash:
tail -f err.log |&
-bash: syntax error near unexpected token `&'
I am attempting to continuously read a file that is being updated by doing a "tail -f" on the file and piping the output to stdin which can then be read by the next shell command
Thnx (4 Replies)
Hi All...
Does anyone know how to pipe the output of a "select" statement from a call to Oracle to a file?
ANy ideas woule be greatly appreciated!
Code is as below...
echo "producing CSV file 2..."
sqlplus -s $username/$password@$database<<EOF
set serveroutput on size 1000000
set... (13 Replies)
Hi.
I have a script like so:
#!/bin/bash
download='php /var/www/last.php'
echo $download
if $downloadHow do I pipe the output of the php file into a variable, as when i run the if statement, it just echos the file output to the screen and does not actually consider the output (it will be... (2 Replies)
Hi All,
I am trying to convert the below Csh code into Perl.
But i have the following error.
Can any expert help ?
Error:
ls: *tac: No such file or directory
Csh
set $ST_file = `ls -rt *$testid*st*|tail -1`;
Perl
my $ST_file = `ls -rt *$testid*st*|tail -1`; (10 Replies)
This is going to be part of a longer script with more features, but I have boiled it down to the one thing that is presently stumping me. The goal is a script which checks for updates to web pages that can be run as a cron job. The script reads (from a tab-delim file) a URL, an MD5 digest, and an... (1 Reply)
Hello everybody,
I need some help here. I have a log file that gets updated every hour approximately.
I want to make some processing on each line which is added in the log file with a program written in PERL.
The problem is that I don't see anything when a line is added in the log file.
I... (6 Replies)
Ok, so there is a perl script that runs as a server, on my local host. It tells me which port to use. I want to pipe that output into my browser so I can do the whole thing with a single command. The problem is, I think, that the program doesn't actually exit cause it's running a server, so...... (6 Replies)
Basically I was wondering if any of you know how to pipe the output of ls to a text file? so in my shell script one of the lines is ls but i want to pipe it into a file called directory listing.
Cheers.
I have tried ls | Directorylisting.txt
but it keeps saying " line 7: DirectoryListing.txt:... (9 Replies)
i have a file seperated each line seperated by newline. For example
alpha
beta
gamma
i am trying to replace the newlines to "," but dont want , present at the end of the line so i am trying the below one liner . but not sure whats wrong but its not working
cat myfile | tr -s '\n' ',' | sed... (9 Replies)
Discussion started by: chidori
9 Replies
LEARN ABOUT SUSE
foreach
foreach(n) Tcl Built-In Commands foreach(n)
__________________________________________________________________________________________________________________________________________________NAME
foreach - Iterate over all elements in one or more lists
SYNOPSIS
foreach varname list body
foreach varlist1 list1 ?varlist2 list2 ...? body
_________________________________________________________________DESCRIPTION
The foreach command implements a loop where the loop variable(s) take on values from one or more lists. In the simplest case there is one
loop variable, varname, and one list, list, that is a list of values to assign to varname. The body argument is a Tcl script. For each
element of list (in order from first to last), foreach assigns the contents of the element to varname as if the lindex command had been
used to extract the element, then calls the Tcl interpreter to execute body.
In the general case there can be more than one value list (e.g., list1 and list2), and each value list can be associated with a list of
loop variables (e.g., varlist1 and varlist2). During each iteration of the loop the variables of each varlist are assigned consecutive
values from the corresponding list. Values in each list are used in order from first to last, and each value is used exactly once. The
total number of loop iterations is large enough to use up all the values from all the value lists. If a value list does not contain enough
elements for each of its loop variables in each iteration, empty values are used for the missing elements.
The break and continue statements may be invoked inside body, with the same effect as in the for command. Foreach returns an empty string.
EXAMPLES
This loop prints every value in a list together with the square and cube of the value:
set values {1 3 5 7 2 4 6 8} ;# Odd numbers first, for fun!
puts "Value Square Cube" ;# Neat-looking header
foreach x $values { ;# Now loop and print...
puts " $x [expr {$x**2}] [expr {$x**3}]"
}
The following loop uses i and j as loop variables to iterate over pairs of elements of a single list.
set x {}
foreach {i j} {a b c d e f} {
lappend x $j $i
}
# The value of x is "b a d c f e"
# There are 3 iterations of the loop.
The next loop uses i and j to iterate over two lists in parallel.
set x {}
foreach i {a b c} j {d e f g} {
lappend x $i $j
}
# The value of x is "a d b e c f {} g"
# There are 4 iterations of the loop.
The two forms are combined in the following example.
set x {}
foreach i {a b c} {j k} {d e f g} {
lappend x $i $j $k
}
# The value of x is "a d e b f g c {} {}"
# There are 3 iterations of the loop.
SEE ALSO
for(n), while(n), break(n), continue(n)
KEYWORDS
foreach, iteration, list, looping
Tcl foreach(n)