07-30-2009
it depends on your file size...
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Hi all you enlightened unix people,
I've been trying to execute a perl script that contains the following line within backticks:
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Hi,
A datafile containing lines such as below needs to be split:
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3. Shell Programming and Scripting
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4. HP-UX
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5. Shell Programming and Scripting
Hi,
I have a script below for extracting xml from a file.
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.
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6. Shell Programming and Scripting
awk "/May 23, 2012 /,0" /var/tmp/datafile
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Hello guys,
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8. Shell Programming and Scripting
Hi,
I have a large number of input files with two columns of numbers.
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83 1453
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99 8482
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9. Shell Programming and Scripting
Good evening
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10. Shell Programming and Scripting
I have the below command which is referring a large file and it is taking 3 hours to run. Can something be done to make this command faster.
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LEARN ABOUT LINUX
getpagesize
GETPAGESIZE(2) Linux Programmer's Manual GETPAGESIZE(2)
NAME
getpagesize - get memory page size
SYNOPSIS
#include <unistd.h>
int getpagesize(void);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
getpagesize():
Since glibc 2.12:
_BSD_SOURCE ||
!(_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600)
Before glibc 2.12:
_BSD_SOURCE || _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
DESCRIPTION
The function getpagesize() returns the number of bytes in a page, where a "page" is the thing used where it says in the description of
mmap(2) that files are mapped in page-sized units.
The size of the kind of pages that mmap(2) uses, is found using
#include <unistd.h>
long sz = sysconf(_SC_PAGESIZE);
(most systems allow the synonym _SC_PAGE_SIZE for _SC_PAGESIZE), or
#include <unistd.h>
int sz = getpagesize();
CONFORMING TO
SVr4, 4.4BSD, SUSv2. In SUSv2 the getpagesize() call is labeled LEGACY, and in POSIX.1-2001 it has been dropped; HP-UX does not have this
call. Portable applications should employ sysconf(_SC_PAGESIZE) instead of this call.
NOTES
Whether getpagesize() is present as a Linux system call depends on the architecture. If it is, it returns the kernel symbol PAGE_SIZE,
whose value depends on the architecture and machine model. Generally, one uses binaries that are dependent on the architecture but not on
the machine model, in order to have a single binary distribution per architecture. This means that a user program should not find
PAGE_SIZE at compile time from a header file, but use an actual system call, at least for those architectures (like sun4) where this depen-
dency exists. Here libc4, libc5, glibc 2.0 fail because their getpagesize() returns a statically derived value, and does not use a system
call. Things are OK in glibc 2.1.
SEE ALSO
mmap(2), sysconf(3)
COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2010-09-20 GETPAGESIZE(2)