I'm not sure you can substitute there. this code works:
awk will barf and quit if you try and redirect into an invalid filename for some reason so check the filename before you do.
The close() is because otherwise, the file will remain open so that if you decide to write to it again later, you'll write a second line instead of overwriting it. So if you were splitting a million rows you could end up with one million open files! plain old awk doesn't have close but nawk should.
Last edited by Corona688; 04-15-2011 at 05:32 PM..
I have written many awk commands which go in multiple lines.
I have this confusion many times.
Some time they work if i dont terminate them with "\" but some time error.
Some time in "if" statements between if and else if i dont use ";" it gives error but sometimes it doesnt.
The below... (4 Replies)
I don't get correct output when I run this command line:
nmap -sP failedhost.com | grep -i failed | awk -F '{print $6}'
I basically want it to return 'failedhost.com' but its just showing the output of the nmap scan. (8 Replies)
Hi I am trying to understand AWK syntax
so I tried this command which gives me the home directory of root
awk 'BEGIN { FS = ":"} {if ($1 == "root") print $6 }' /etc/passwd
I would know what are the following commands doing. The first one prints all /etc/passwd, second prints nothing.
... (4 Replies)
Little bit confusing while using awk :confused::confused:
In Sed while pattern search we can use "(double quotes)
i mean
$a=hello
$cat file.txt |sed -n "/$a/p"this thing work fine But if i use it in awk it's not working How could i do the substitution of pattern by a variables and the... (1 Reply)
i have a ksh code that needs to be written in AWK. can someone please help me here? :(
if }" | grep -c "$2") -gt 0 ] ; then
print - "found $2 in array ignore"
else
print - "did not find $2 in array ignore"
fi
ignore=4ty56r
ignore=er45ty
.
.
.
ignore=frhtg2 (27 Replies)
I have a file which is comma separated and has quotes. I can use this command and
awk -F"," '{ if ($4=="01" print $0 }' test.txt
But this doesn't fetch me the data.since it has quotes.
If the data has no quotes,the above command works fine.
In Unix you can skip quote \" but this doesn't work.... (7 Replies)
Hi, I would like to know what is the correct syntax to perform a function in awk. Although I have seen several examples, not get it to work, this is what I'm trying:
#!/bin/bash
awk
function multi (number) {
return number * 3
}
print multi (4)Thanks (2 Replies)
Hello,
I have perl script,which take some part of data in the file.
the below command works fine in normal cmd prompt.
`awk '/CDI/ && // && !/Result for/ {print $3 $5 > "final.txt"}' datalist.txt`;
`nawk -F"" '{print $2}' finalcdi.txt`;
But not working.
Please use code tags, thanks. (5 Replies)
Hello Experts:
While writing a script to help one of the posts on here, I end up writing a wrong one. I am very much eager to know how this can be corrected.
Aim was to not print specified columns - lets say out of 100 fields, need to print all but 5th, 10th, 15th columns.
Someone already... (13 Replies)
awk -F, ' NR>1 {
BEGIN{
chr=$2
}
END{
for (k in chr) {print k}
}
} ' $gene_file
I've a really simple code. I want to store gene name and it's chromosome and in the end print them.
I'm skipping line one as it contains headers.
But I don't know why I get error as: (2 Replies)
Discussion started by: genome
2 Replies
LEARN ABOUT CENTOS
close
close(n) Tcl Built-In Commands close(n)
__________________________________________________________________________________________________________________________________________________NAME
close - Close an open channel
SYNOPSIS
close channelId
_________________________________________________________________DESCRIPTION
Closes the channel given by channelId.
ChannelId must be an identifier for an open channel such as a Tcl standard channel (stdin, stdout, or stderr), the return value from an
invocation of open or socket, or the result of a channel creation command provided by a Tcl extension.
All buffered output is flushed to the channel's output device, any buffered input is discarded, the underlying file or device is closed,
and channelId becomes unavailable for use.
If the channel is blocking, the command does not return until all output is flushed. If the channel is nonblocking and there is unflushed
output, the channel remains open and the command returns immediately; output will be flushed in the background and the channel will be
closed when all the flushing is complete.
If channelId is a blocking channel for a command pipeline then close waits for the child processes to complete.
If the channel is shared between interpreters, then close makes channelId unavailable in the invoking interpreter but has no other effect
until all of the sharing interpreters have closed the channel. When the last interpreter in which the channel is registered invokes close,
the cleanup actions described above occur. See the interp command for a description of channel sharing.
Channels are automatically closed when an interpreter is destroyed and when the process exits. Channels are switched to blocking mode, to
ensure that all output is correctly flushed before the process exits.
The command returns an empty string, and may generate an error if an error occurs while flushing output. If a command in a command pipe-
line created with open returns an error, close generates an error (similar to the exec command.)
EXAMPLE
This illustrates how you can use Tcl to ensure that files get closed even when errors happen by combining catch, close and return:
proc withOpenFile {filename channelVar script} {
upvar 1 $channelVar chan
set chan [open $filename]
catch {
uplevel 1 $script
} result options
close $chan
return -options $options $result
}
SEE ALSO
file(n), open(n), socket(n), eof(n), Tcl_StandardChannels(3)KEYWORDS
blocking, channel, close, nonblocking
Tcl 7.5 close(n)