Third, $1 isn't a command name so you can't pipe into it. Pipes are for commands, files use redirection.
Fourth, this doesn't work in general. It's only working here because of special properties of the sort command: It reads the entire file before writing any output, hence reads the entire file before uniq is allowed to truncate it. This will NOT work:
So in general, redirecting to the same file you're reading from is a bad idea. It only works in very special circumstances.
Hi. I hope someone can help me with this problem.
Being a novice to Unix, I editted my crontab directly
by typing " crontab -e ". Well, I needed to make some
changes so, I typed " crontab -r ". Now I have no crontab,
and I can't seem to get crontab to write a new file.
I' ve tried:
vi... (4 Replies)
Hi,
I needed space on a FS, and when I've added the space on the filesystem, I did it trough the regular smitty fs inteface and not with smitty cl_lvm.
Can someone help me to repair the situat before a faileover happen ?
Thanks for your help,:mad: (13 Replies)
Hi there,
Can anyone help me find the correct expression for sed.
I want to repace iface eth0 inet wathever
with iface eth0 inet static
Thanks for your help
Santiago (5 Replies)
Let's say someone accidentally renamed the lib directory in Solaris 8, and now they cannot get into the terminal or even rename the folder via file manager.What would one do? (37 Replies)
hi,
instead of typing crontab -e i gave crontab -r and hit enter. So i lost all my scripts.
Is there any way to restore the deleted scripts?
Please help me out
Thanks
Ajay (3 Replies)
Hi everyone !
I have a file wich look like this :
>Sis01
> Sis02
...
>Sis44
I want to separe each paragraphe in a different file, so I decide to use the "FOR" loop + sed.
for f in {01..44}
do (5 Replies)
Hi there can anyone help me to spot my mistake and please explain why it appears
My code :
#!/usr/bin/gawk -f
BEGIN { bytes =0}
{ temp=$(grep "datafeed\.php" | cut -d" " -f8)
bytes += temp}
END { printf "Number of bytes: %d\n", bytes }
when I am running ./q411 an411
an411:
... (6 Replies)
Hi,
I want to start MY_PROGRAM in a bash script with additional parameters given in the CONFIGURATION_ARRAY.
IFS="'"
CONFIGURATION_ARRAY=( '-N 0 -m 0' '-N 0 -m 1' )
for configuration in ${CONFIGURATION_ARRAY}
do
//DEBUG
N=${configuration%-*} //-N 0
M=-${configuration##*-} //-m 0... (5 Replies)
#!/bin/bash
source=/to_be_archived
dest=/archived
echo "is this archive for an audio tar press (t) or an audio directory press (d)"
read option
case $option in
d)
cd "$source"
echo "please specify full path to directory you want to be... (6 Replies)
Discussion started by: robertkwild
6 Replies
LEARN ABOUT CENTOS
uniq
UNIQ(1) User Commands UNIQ(1)NAME
uniq - report or omit repeated lines
SYNOPSIS
uniq [OPTION]... [INPUT [OUTPUT]]
DESCRIPTION
Filter adjacent matching lines from INPUT (or standard input), writing to OUTPUT (or standard output).
With no options, matching lines are merged to the first occurrence.
Mandatory arguments to long options are mandatory for short options too.
-c, --count
prefix lines by the number of occurrences
-d, --repeated
only print duplicate lines, one for each group
-D, --all-repeated[=METHOD]
print all duplicate lines groups can be delimited with an empty line METHOD={none(default),prepend,separate}
-f, --skip-fields=N
avoid comparing the first N fields
--group[=METHOD]
show all items, separating groups with an empty line METHOD={separate(default),prepend,append,both}
-i, --ignore-case
ignore differences in case when comparing
-s, --skip-chars=N
avoid comparing the first N characters
-u, --unique
only print unique lines
-z, --zero-terminated
end lines with 0 byte, not newline
-w, --check-chars=N
compare no more than N characters in lines
--help display this help and exit
--version
output version information and exit
A field is a run of blanks (usually spaces and/or TABs), then non-blank characters. Fields are skipped before chars.
Note: 'uniq' does not detect repeated lines unless they are adjacent. You may want to sort the input first, or use 'sort -u' without
'uniq'. Also, comparisons honor the rules specified by 'LC_COLLATE'.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report uniq translation bugs to <http://translationproject.org/team/>
AUTHOR
Written by Richard M. Stallman and David MacKenzie.
COPYRIGHT
Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO comm(1), join(1), sort(1)
The full documentation for uniq is maintained as a Texinfo manual. If the info and uniq programs are properly installed at your site, the
command
info coreutils 'uniq invocation'
should give you access to the complete manual.
GNU coreutils 8.22 June 2014 UNIQ(1)