I am working with single line file with 589744523 characters having 542 "^M" (line feed) character.
I want to make 542 different lines file from the single line file thr. shell program only (it can be done thr vi command)
rd
anil
sorry for duplicate post previously, actually i don,t know... (6 Replies)
Hi,
I want to remove duplicate records including the first line based on column1. For example
inputfile(filer.txt):
-------------
1,3000,5000
1,4000,6000
2,4000,600
2,5000,700
3,60000,4000
4,7000,7777
5,999,8888
expected output:
----------------
3,60000,4000
4,7000,7777... (5 Replies)
I was reading this thread. It looks like a simpler way to say this is to only keep uniq lines based on field or column 1.
https://www.unix.com/shell-programming-scripting/165717-removing-duplicate-records-file-based-single-column.html
Can someone explain this command please? How are there no... (5 Replies)
I have two files like ABC_DEF_yyyyymmdd_hhmiss_XXX.txt and ABC_DEF_yyyyymmdd_hhmiss_YYY.txt. The date part is going to be changing everytime. How do i remove this date part of the file and create a single file like ABC_DEF_XXX.txt. (8 Replies)
Hi friends
please help me on below,
i have 5 files like below
file1 is
x 10
y 20
z 15
file2 is
x 100
z 245
file3 is
y 78
z 23
file4 is
x 100 (3 Replies)
hdr=$(cut -c1 $path$file|head -1)#extract header”H”
trl=$(cut -c|path$file|tail -1)#extract trailer “T”
SplitFile=$(cut -c 50-250 $path 1$newfile |sed'$/ *$//' head -1')# to trim white space and extract table name
If; then # start loop if it is a header
While read I #read file
Do... (4 Replies)
Dear all,
I am editing a tri-lingual dictionary for open source which has the following data structure
English headwords <Tab>Devanagari Headwords<Tab>PersoArabic headwords
as in the example below
to mark, to number अंगणु (اَنگَڻُ)
The English headword entry has at times more than one word,... (2 Replies)
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)
I am trying to consolidate multiple information files (<hostname>.Linux.nfslist) into one file so that I can import it into Excel. I can get the file contents with cat *Linux.nfslist >> nfslist.txt. I need each line prefaced with the hostname. I am unsure how to do this.
--- Post updated at... (5 Replies)
Discussion started by: Kentlee65
5 Replies
LEARN ABOUT X11R4
posix_madvise
POSIX_MADVISE(3) Linux Programmer's Manual POSIX_MADVISE(3)NAME
posix_madvise - give advice about patterns of memory usage
SYNOPSIS
#include <sys/mman.h>
int posix_madvise(void *addr, size_t len, int advice);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
posix_madvise():
_POSIX_C_SOURCE >= 200112L
DESCRIPTION
The posix_madvise() function allows an application to advise the system about its expected patterns of usage of memory in the address range
starting at addr and continuing for len bytes. The system is free to use this advice in order to improve the performance of memory
accesses (or to ignore the advice altogether), but calling posix_madvise() shall not affect the semantics of access to memory in the speci-
fied range.
The advice argument is one of the following:
POSIX_MADV_NORMAL
The application has no special advice regarding its memory usage patterns for the specified address range. This is the default
behavior.
POSIX_MADV_SEQUENTIAL
The application expects to access the specified address range sequentially, running from lower addresses to higher addresses.
Hence, pages in this region can be aggressively read ahead, and may be freed soon after they are accessed.
POSIX_MADV_RANDOM
The application expects to access the specified address range randomly. Thus, read ahead may be less useful than normally.
POSIX_MADV_WILLNEED
The application expects to access the specified address range in the near future. Thus, read ahead may be beneficial.
POSIX_MADV_DONTNEED
The application expects that it will not access the specified address range in the near future.
RETURN VALUE
On success, posix_madvise() returns 0. On failure, it returns a positive error number.
ERRORS
EINVAL addr is not a multiple of the system page size or len is negative.
EINVAL advice is invalid.
ENOMEM Addresses in the specified range are partially or completely outside the caller's address space.
VERSIONS
Support for posix_madvise() first appeared in glibc version 2.2.
CONFORMING TO
POSIX.1-2001.
NOTES
POSIX.1 permits an implementation to generate an error if len is 0. On Linux, specifying len as 0 is permitted (as a successful no-op).
In glibc, this function is implemented using madvise(2). However, since glibc 2.6, POSIX_MADV_DONTNEED is treated as a no-op, because the
corresponding madvise(2) value, MADV_DONTNEED, has destructive semantics.
SEE ALSO madvise(2), posix_fadvise(2)COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the
latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
Linux 2017-09-15 POSIX_MADVISE(3)