Sponsored Content
Top Forums Shell Programming and Scripting How to read a multiple lines from a file n executing them? Post 302481929 by rbatte1 on Monday 20th of December 2010 08:20:56 AM
Old 12-20-2010
anurag.singh is correct in what is said. The question we have to be clear on is why you want to
Code:
ls -l|cut -c 58-88 > file1.txt

I assume that this is so you get just the names of the files from an ls -l, but this is just the same as output from ls sent to a file or ls -1 (flag is minus one) to be used in a loop as described.

So, what are you trying to get? If it is just files from a directory, you might also confuse yourself if you write the temporary file there too. Editing the file with con.ksh mid program when that is the input file might have unpredictable results too.

You also run the risk of having a file that is longer than the 31 characters you are limiting this to. If you have a file called this_is_a_very_long_name_for_a_file, then you would try to run
Code:
con.ksh this_is_a_very_long_name_for_a_

and presumably get an error meaning file not found.

Another way to approach this is to use the find command. As such, you can exclude links, directories, pipe files etc. by specifying you only want regular files:
Code:
find . -type f -exec con.ksh {} \;

This looks in the current directory (the dot) for a regular files (-type f) and then executes con.ksh with each as an arguement (-exec con.ksh {} \Smilie The trailing \; marks the end of the -exec part of the command and the find will error if it is missing.



I hope that this is useful, but please write back if this I have missed the point.


Robin
Liverpool/Blackburn
UK
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

read and match multiple lines in perl

Could any one tell me how to read and match multiple lines in perl? Did this code below still work in this situation? while (<FILE>) { if (/ /) { } } Thanks a lot! (5 Replies)
Discussion started by: zx1106
5 Replies

2. Shell Programming and Scripting

How to read multiple lines from Std Input into an array

Hi All, Does anyone know how to read multiple lines from standard input into an array and then iterate a loop for all the lines read. Below is an example pseudocode: I need the below filenames to be read by the script into an array or something similar: And then in the script, I... (9 Replies)
Discussion started by: bharath.gct
9 Replies

3. UNIX for Dummies Questions & Answers

When reading a csv file, counter to read 20 lines and wait for minute then read next 20 till end

Hello All, i am a newbie and need some help when reading a csv file in a bourne shell script. I want to read 10 lines, then wait for a minute and then do a reading of another 10 lines and so on in the same way. I want to do this till the end of file. Any inputs are appreciated ... (3 Replies)
Discussion started by: victor.s
3 Replies

4. Shell Programming and Scripting

read one line file and separate into multiple lines

I have one long line text with semicolon used as separator between values in that line. Now, I want to separate the line into multiple line right after every 29th field. example input line: ... (2 Replies)
Discussion started by: erlanq
2 Replies

5. Shell Programming and Scripting

read one line file and separate into multiple lines

I have one long line text with semicolon used as separator between values in that line. Now, I want to separate the line into multiple line right after every 29th field. example input line: ... (1 Reply)
Discussion started by: erlanq
1 Replies

6. Shell Programming and Scripting

Awk match multiple columns in multiple lines in single file

Hi, Input 7488 7389 chr1.fa chr1.fa 3546 9887 chr5.fa chr9.fa 7387 7898 chrX.fa chr3.fa 7488 7389 chr21.fa chr3.fa 7488 7389 chr1.fa chr1.fa 3546 9887 chr9.fa chr5.fa 7898 7387 chrX.fa chr3.fa Desired Output 7488 7389 chr1.fa chr1.fa 2 3546 9887 chr5.fa chr9.fa 2... (2 Replies)
Discussion started by: jacobs.smith
2 Replies

7. Shell Programming and Scripting

read the lines of multiple files

I am trying to create a script which will read 2 files and use the lines of file 1 for each line on file 2. here's my sample code cat $SBox | while read line do cat $Date | while read line do $SCRIPTEXE <line from first file> $2 <line from 2nd file> ... (12 Replies)
Discussion started by: khestoi
12 Replies

8. Shell Programming and Scripting

Executing multiple commands in a file at same time

Hi Am having file.ksh as below wc -l file1.txt wc -l file2.txt wc -l file3.txt wc -l file4.txt i want all the commands in this file to execute in same time please help Thanks in advance (1 Reply)
Discussion started by: ragu.selvaraj
1 Replies

9. Shell Programming and Scripting

Read multiple lines at a time from file

Hello All, I have a file like below.... dn: cn=user1,ou=org,o=org cn=user1 uid=user1 cn=user2,ou=org,o=org cn=user2 uid=user2 cn=user3,ou=org,o=org cn=user3 cn=user33 uid=user3 cn=user4,ou=org,o=org cn=user4 uid=user4 (6 Replies)
Discussion started by: s_linux
6 Replies

10. Shell Programming and Scripting

Removing multiple lines from input file, if multiple lines match a pattern.

GM, I have an issue at work, which requires a simple solution. But, after multiple attempts, I have not been able to hit on the code needed. I am assuming that sed, awk or even perl could do what I need. I have an application that adds extra blank page feeds, for multiple reports, when... (7 Replies)
Discussion started by: jxfish2
7 Replies
TRACE-CMD-RESTORE(1)													      TRACE-CMD-RESTORE(1)

NAME
trace-cmd-restore - restore a failed trace record SYNOPSIS
trace-cmd restore [OPTIONS] [command] cpu-file [cpu-file ...] DESCRIPTION
The trace-cmd(1) restore command will restore a crashed trace-cmd-record(1) file. If for some reason a trace-cmd record fails, it will leave a the per-cpu data files and not create the final trace.dat file. The trace-cmd restore will append the files to create a working trace.dat file that can be read with trace-cmd-report(1). When trace-cmd record runs, it spawns off a process per CPU and writes to a per cpu file usually called trace.dat.cpuX, where X represents the CPU number that it is tracing. If the -o option was used in the trace-cmd record, then the CPU data files will have that name instead of the trace.dat name. If a unexpected crash occurs before the tracing is finished, then the per CPU files will still exist but there will not be any trace.dat file to read from. trace-cmd restore will allow you to create a trace.dat file with the existing data files. OPTIONS
-c Create a partial trace.dat file from the machine, to be used with a full trace-cmd restore at another time. This option is useful for embedded devices. If a server contains the cpu files of a crashed trace-cmd record (or trace-cmd listen), trace-cmd restore can be executed on the embedded device with the -c option to get all the stored information of that embedded device. Then the file created could be copied to the server to run the trace-cmd restore there with the cpu files. If *-o* is not specified, then the file created will be called 'trace-partial.dat'. This is because the file is not a full version of something that trace-cmd-report(1) could use. -t tracing_dir Used with -c, it overrides the location to read the events from. By default, tracing information is read from the debugfs/tracing directory. -t will use that location instead. This can be useful if the trace.dat file to create is from another machine. Just tar -cvf events.tar debugfs/tracing and copy and untar that file locally, and use that directory instead. -k kallsyms Used with -c, it overrides where to read the kallsyms file from. By default, /proc/kallsyms is used. -k will override the file to read the kallsyms from. This can be useful if the trace.dat file to create is from another machine. Just copy the /proc/kallsyms file locally, and use -k to point to that file. -o output' By default, trace-cmd restore will create a trace.dat file (or trace-partial.dat if -c is specified). You can specify a different file to write to with the -o option. -i input By default, trace-cmd restore will read the information of the current system to create the initial data stored in the trace.dat file. If the crash was on another machine, then that machine should have the trace-cmd restore run with the -c option to create the trace.dat partial file. Then that file can be copied to the current machine where trace-cmd restore will use -i to load that file instead of reading from the current system. EXAMPLES
If a crash happened on another box, you could run: $ trace-cmd restore -c -o box-partial.dat Then on the server that has the cpu files: $ trace-cmd restore -i box-partial.dat trace.dat.cpu0 trace.dat.cpu1 This would create a trace.dat file for the embedded box. SEE ALSO
trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1), trace-cmd-start(1), trace-cmd-stop(1), trace-cmd-extract(1), trace-cmd-reset(1), trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1) AUTHOR
Written by Steven Rostedt, <rostedt@goodmis.org[1]> RESOURCES
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git COPYING
Copyright (C) 2010 Red Hat, Inc. Free use of this software is granted under the terms of the GNU Public License (GPL). NOTES
1. rostedt@goodmis.org mailto:rostedt@goodmis.org 06/11/2014 TRACE-CMD-RESTORE(1)
All times are GMT -4. The time now is 04:39 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy