cat header sortedfile > newfile, the operation takes 2 minutes as the sorted file is over 400mb.
I have noticed that when I sort the 400mb unsorted file, this only takes 14 seconds to create the output.
Did that 14 second sort write everything to disk too by redirection or just output to your screen? Question might sound dumb, but just the be sure that it is written to disk too.
So, I have a file that has some duplicate lines. The file has a header line that I would like to keep at the top.
I could do this by extracting the header from the file, 'sort -u' the remaining lines, and recombine them. But they are quite big, so if there is a way to do it with a single... (1 Reply)
Hi Experts,
I want to Sort the data in fixed width file where i have Header and Footer also in file.
I m using below commad to do the sort based on field satarting from 15 position to 17 position , but it is not ignoring the Header and Footer of the file while sorting. In the output i am... (5 Replies)
I am having report file with header and footer . The details in between header and footer are separated by a pipe charater. I want to sort the file by considering multiple columns in between header and footer.
pls help (4 Replies)
How to sort a tab delimited file first on col1 and then on col2. Also I need to keep the header intact.
file.txt
val1 val2 val3 val4
a b c d
m n o p
e f g h
i j k l
... (3 Replies)
My files location
Dir=/pp/Output/Test/
I have 100 .txt files on above location.
I want add header "pt all" on each file.
Sample Text file
Hi
Kalol
Jt all
q
Output i want
lt all
Kalol
Jt all (2 Replies)
Hi,
I have an input like this
1 2 3 4
2 3 4 5
4 5 6 7
I would like to count the no. of columns and print a header with a prefix "Col".
I would also like to count the no. of rows and print as first column with each line number with a prefix "Row"
So, my output would be
... (2 Replies)
Hi,
I'm trying to sort 2 different .txt tab delimited files with the command line:
sort -k 1b,1 inputfile > outputfile
But doing that i'm also sorting the header (that ends at the end of my file).
How can i sort a .txt file without sorting the header but conserving the header in the... (3 Replies)
I have several las files with a header and each file start Version and text and before the data starts end up with ~Ascii, then the numbers starts:
-------------------------------------------------------------------------
Code:
~Version
.....text....
~Ascii
2 abc 230 1 name
1 abc ... (1 Reply)
I have several las files with a header and each file start Version and text and before the data starts end up with ~Ascii, then the numbers starts:
-------------------------------------------------------------------------
~Version
.....text....
~Ascii
2 abc 230 1 name
1 abc 400 1... (17 Replies)
Hi,
I am using SUN SOLARIS (SunOS sun4v sparc SUNW, T5240).
I have a huge data file with header and trailer. This file gets used into an ETL process. ETL skips the header record (which is the first record of the file) and loads the rest of the record. The file can be delimited (comma,... (5 Replies)
Discussion started by: Saanvi1
5 Replies
LEARN ABOUT HPUX
readahead
readahead(8) System Manager's Manual readahead(8)NAME
readahead - file preloader for boot process optimization
SYNOPSIS
readahead [options] <file-list> [another-file-list [...]]
DESCRIPTION
readahead is a files preloader designed to optimize the disk I/O during the boot process.
OPTIONS -b, --build
build optimised files list only, without sorting.
-s, --sort
build and sort list of files only (implies -b).
-o, --output <file>
write sorted list of files to file.
-d, --dont-sort
preload files described by an already sorted files list.
-h, --help
print the usage information.
-v, --verbose
enable the verbose mode.
-t, --timing
report time spent on each operation.
-m, --maxsize <max size>
maximum size in KiB a file can be in order to be preloaded, default is 10240.
<file-list> [another-file-list [...]]
One or more files containing the list of files to be preloaded or sorted. The files list can be generated by readahead-collector(8).
FILES
/etc/default/readahead-fedora
SEE ALSO readahead-collector(8), readahead(2),
AUTHORS
Arjan van de Ven <arjan@infradead.org>,
Ziga Mahkovec <ziga.mahkovec@klika.si>, Karel Zak <kzak@redhat.com>,
This manual page was written by Raphael Geissert <geissert@debian.org>
July 2011 readahead(8)