04-02-2013
Display sorted list using sed command
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
Write a command line that will display a sorted list of logged in users. Just display the username and no other information. To accomplish this task you must use the sed command (The cut command is not allowed).
2. Relevant commands, code, scripts, algorithms:
Must use the sed command.
3. The attempts at a solution (include all code and scripts):
I am not sure how to even go about this question. Still really new at shell scripting.
4. Complete Name of School (University), City (State), Country, Name of Professor, and Course Number (Link to Course):
Calvin College, Grand Rapids MI, USA, Johnson, CO 142
Note: Without school/professor/course information, you will be banned if you post here! You must complete the entire template (not just parts of it).
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I'm trying to execute a single shell command that will give me a sorted list of all the users currently logged into the system, displaying the users name as it appears in /etc/passwd.
I've tried
awk -F: '{print $1}' /etc/passwd | xargs finger -s | cut -c11-28 | uniq
This list whoever does... (7 Replies)
Discussion started by: kungfuice
7 Replies
2. UNIX for Dummies Questions & Answers
#!/bin/bash
{ && ; } || {
echo "Must enter between 1 and 5 parameters"
exit 1
}
for P
do
echo $P >> /tmp/task3
done
echo "SORTED: $(sort -n -r /tmp/task3)"
rm -f /tmp/task3 (2 Replies)
Discussion started by: knc9233
2 Replies
3. Shell Programming and Scripting
Hi,
i have to make a command in unix system which make a sorted list by cpu time (not %cpu ). If the application exists more than a time I would like to keep only one copy.
Could you help me please ???
P.s : I am trying --> ps aux --sort -%cpu | uniq
but I understand that is wrong (5 Replies)
Discussion started by: petros55
5 Replies
4. UNIX for Dummies Questions & Answers
the sorting is based on name of file,
file size
modification time stamps o f file
it should dislay the output in the following format
"." and ".." enteries should be ignored
please give some idea how to do it (1 Reply)
Discussion started by: pappu kumar jha
1 Replies
5. Shell Programming and Scripting
if i want to display the contents of a file between say line number 3 and 10 then i use the following command
sed -n '3,10p' filename
if this 3 was contained in x and 10 was contained in y then how wud this command modified?
sed -n '$x,$yp' filename does not work..please advise (2 Replies)
Discussion started by: arindamlive
2 Replies
6. Shell Programming and Scripting
I have a sorted list (python) and I want to insert a string if it matches the pattern in list.
Example :
Sorted List
Above list is in sorted order. I need to insert a name in sorted order and also if the name already exist then it should be inserted before the existing... (1 Reply)
Discussion started by: pratapsingh
1 Replies
7. Shell Programming and Scripting
Hi All,
Following is my issue.
$MAIL_DOC = test.txt
test.txt contains the following text .
This process was executed in the %INSTANCE% instance on %RUNDATE%.
I am trying to execute the following script
var=`echo $ORACLE_SID | tr `
NOW=$(date +"%D")
sed -e... (3 Replies)
Discussion started by: megha2525
3 Replies
8. Shell Programming and Scripting
Hello friends! I am working a Psychology/Neuro* project where I am sorting inline citations by category. The final step of the process has me a little stuck. I need to take citations from a text list and sort them in another text file.
Here is a file X example... (1 Reply)
Discussion started by: danbroz
1 Replies
9. UNIX for Beginners Questions & Answers
Hi Team,
Am a newbie to Unix. As I would like to see the Server Name,Owner Name ( not numeric form), Group Name ( not numeric ID), ROOT path.
I would like to send this list as an attachment to my personal mail. Can any one please help me out to to resolve this .
Here is the sample result... (6 Replies)
Discussion started by: vasuvv
6 Replies
10. HP-UX
Hello,
I've been doing Linux and AIX administration for years, but I'm very new to HPUX. We have an old audit process which involves someone manually using sam to generate user lists. I'd like to kill that old process with fire...
But...
After working a bit in the morning to try and pull... (3 Replies)
Discussion started by: Celt1977
3 Replies
regex(1F) FMLI Commands regex(1F)
NAME
regex - match patterns against a string
SYNOPSIS
regex [-e] [ -v "string"] [ pattern template] ... pattern [template]
DESCRIPTION
The regex command takes a string from the standard input, and a list of pattern / template pairs, and runs regex() to compare the string
against each pattern until there is a match. When a match occurs, regex writes the corresponding template to the standard output and
returns TRUE. The last (or only) pattern does not need a template. If that is the pattern that matches the string, the function simply
returns TRUE. If no match is found, regex returns FALSE.
The argument pattern is a regular expression of the form described in regex(). In most cases, pattern should be enclosed in single quotes
to turn off special meanings of characters. Note that only the final pattern in the list may lack a template.
The argument template may contain the strings $m0 through $m9, which will be expanded to the part of pattern enclosed in ( ... )$0 through
( ... )$9 constructs (see examples below). Note that if you use this feature, you must be sure to enclose template in single quotes so
that FMLI does not expand $m0 through $m9 at parse time. This feature gives regex much of the power of cut(1), paste(1), and grep(1), and
some of the capabilities of sed(1). If there is no template, the default is $m0$m1$m2$m3$m4$m5$m6$m7$m8$m9.
OPTIONS
The following options are supported:
-e Evaluates the corresponding template and writes the result to the standard output.
-v "string" Uses string instead of the standard input to match against patterns.
EXAMPLES
Example 1: Cutting letters out of a string
To cut the 4th through 8th letters out of a string (this example will output strin and return TRUE):
`regex -v "my string is nice" '^.{3}(.{5})$0' '$m0'`
Example 2: Validating input in a form
In a form, to validate input to field 5 as an integer:
valid=`regex -v "$F5" '^[0-9]+$'`
Example 3: Translating an environment variable in a form
In a form, to translate an environment variable which contains one of the numbers 1, 2, 3, 4, 5 to the letters a, b, c, d, e:
value=`regex -v "$VAR1" 1 a 2 b 3 c 4 d 5 e '.*' 'Error'`
Note the use of the pattern '.*' to mean "anything else".
Example 4: Using backquoted expressions
In the example below, all three lines constitute a single backquoted expression. This expression, by itself, could be put in a menu defini-
tion file. Since backquoted expressions are expanded as they are parsed, and output from a backquoted expression (the cat command, in this
example) becomes part of the definition file being parsed, this expression would read /etc/passwd and make a dynamic menu of all the login
ids on the system.
`cat /etc/passwd | regex '^([^:]*)$0.*$' '
name=$m0
action=`message "$m0 is a user"`'`
DIAGNOSTICS
If none of the patterns match, regex returns FALSE, otherwise TRUE.
NOTES
Patterns and templates must often be enclosed in single quotes to turn off the special meanings of characters. Especially if you use the
$m0 through $m9 variables in the template, since FMLI will expand the variables (usually to "") before regex even sees them.
Single characters in character classes (inside []) must be listed before character ranges, otherwise they will not be recognized. For exam-
ple, [a-zA-Z_/] will not find underscores (_) or slashes (/), but [_/a-zA-Z] will.
The regular expressions accepted by regcmp differ slightly from other utilities (that is, sed, grep, awk, ed, and so forth).
regex with the -e option forces subsequent commands to be ignored. In other words, if a backquoted statement appears as follows:
`regex -e ...; command1; command2`
command1 and command2 would never be executed. However, dividing the expression into two:
`regex -e ...``command1; command2`
would yield the desired result.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
awk(1), cut(1), grep(1), paste(1), sed(1), regcmp(3C), attributes(5)
SunOS 5.10 12 Jul 1999 regex(1F)