Insert a line in a file by deleting that line from another file
Hi all,
I have a huge file(size more that 5GB).
I want to do some manupulation with the records and write to another file.
As the size of the file is huge and there is a space constraint in that directory, I want to delete that record from first file after writing it in to second file.
Example:-
Code:
cat first.dat | while read line
do
echo $line| ......... >> second.dat
# Here after writing to second file i want to delete the same record from first.dat
done
can anyone please help me on this???
thanks in adv....
Last edited by Scott; 11-15-2012 at 04:58 PM..
Reason: Code tags, again
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Hi friends, here is my problem.
I have three files like this..
cat file1.txt
=======
unix is best
unix is best
linux is best
unix is best
linux is best
linux is best
unix is best
unix is best
cat file2.txt
========
Windows performs better
Mac OS performs better
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Hi all,
I'm new to scripting.. facing some problems while inserting content of a file into another file...
I want to insert content of a file (file2) into file1, before first occurrence of "line starts with pattern" in file1
file1
======
working on linux
its unix world
working on... (14 Replies)
Discussion started by: Jagadeesh Kumar
14 Replies
LEARN ABOUT LINUX
alloc_hugepages
ALLOC_HUGEPAGES(2) Linux Programmer's Manual ALLOC_HUGEPAGES(2)NAME
alloc_hugepages, free_hugepages - allocate or free huge pages
SYNOPSIS
void *alloc_hugepages(int key, void *addr, size_t len,
int prot, int flag);
int free_hugepages(void *addr);
DESCRIPTION
The system calls alloc_hugepages() and free_hugepages() were introduced in Linux 2.5.36 and removed again in 2.5.54. They existed only on
i386 and ia64 (when built with CONFIG_HUGETLB_PAGE). In Linux 2.4.20 the syscall numbers exist, but the calls fail with the error ENOSYS.
On i386 the memory management hardware knows about ordinary pages (4 KiB) and huge pages (2 or 4 MiB). Similarly ia64 knows about huge
pages of several sizes. These system calls serve to map huge pages into the process's memory or to free them again. Huge pages are locked
into memory, and are not swapped.
The key argument is an identifier. When zero the pages are private, and not inherited by children. When positive the pages are shared
with other applications using the same key, and inherited by child processes.
The addr argument of free_hugepages() tells which page is being freed: it was the return value of a call to alloc_hugepages(). (The memory
is first actually freed when all users have released it.) The addr argument of alloc_hugepages() is a hint, that the kernel may or may not
follow. Addresses must be properly aligned.
The len argument is the length of the required segment. It must be a multiple of the huge page size.
The prot argument specifies the memory protection of the segment. It is one of PROT_READ, PROT_WRITE, PROT_EXEC.
The flag argument is ignored, unless key is positive. In that case, if flag is IPC_CREAT, then a new huge page segment is created when
none with the given key existed. If this flag is not set, then ENOENT is returned when no segment with the given key exists.
RETURN VALUE
On success, alloc_hugepages() returns the allocated virtual address, and free_hugepages() returns zero. On error, -1 is returned, and
errno is set appropriately.
ERRORS
ENOSYS The system call is not supported on this kernel.
FILES
/proc/sys/vm/nr_hugepages Number of configured hugetlb pages. This can be read and written.
/proc/meminfo Gives info on the number of configured hugetlb pages and on their size in the three variables HugePages_Total,
HugePages_Free, Hugepagesize.
CONFORMING TO
These calls are specific to Linux on Intel processors, and should not be used in programs intended to be portable.
NOTES
These system calls are gone; they existed only in Linux 2.5.36 through to 2.5.54. Now the hugetlbfs file system can be used instead. Mem-
ory backed by huge pages (if the CPU supports them) is obtained by using mmap(2) to map files in this virtual file system.
The maximal number of huge pages can be specified using the hugepages= boot parameter.
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 2007-05-31 ALLOC_HUGEPAGES(2)