Hi all,
Does anybody know or guide me on how to remove the first N bytes and the last N bytes from a binary file? Is there any AWK or SED or any command that I can use to achieve this?
Your help is greatly appreciated!!
Best Regards,
Naveen. (1 Reply)
Hello,
I have come across the necessity for me to deal with binary sequences and I had a few questions.
1- Does any UNIX scripting language provide any tool or command for converting text data to binary sequences? Example of binary sequence: "0x97 0x93 0x85 0x40 0xd5 0xd6 0xd7"
2- If I want... (2 Replies)
Hi,
I have an one-line file consisting of a sequence of 660 letters. I would like to extract 9-letter blocks iteratively:
ASDFGHJKLQWERTYUIOPZXCVBNM
first block: ASDFGHJKL
1nd block: SDFGHJKLQ
What I have so far only gives me the first block, can anyone please explain why?
cat... (7 Replies)
Hi,
This is part of a large text file I need to separate out.
I'd like some help to build a shell script that will extract the text between sets of dashed lines, write that to a new file using the whole or part of the first text string as the new file name, then move on to the next one and... (7 Replies)
The title is clear: why does ext3 allocate 8 blocks for files that are few bytes long?
If I create a file named "test", put a few chars in it, and then I run:
stat test
I get that "Blocks: 8"
I searched in the web and found that ext does that, it allocates 8 blocks even if It doesn't need... (4 Replies)
Hello guys. I really hope someone will help me with this one..
So, I have to write this script who:
- creates a file home/student/vmdisk of 10 mb
- formats that file to ext3
- mounts that partition to /mnt/partition
- creates a file /mnt/partition/data. In this file, there will... (1 Reply)
Hi,
I have a file with more than 28000 records and it looks like below..
>mm10_refflat_ABCD range=chr1:1234567-2345678
tgtgcacactacacatgactagtacatgactagac....so on
>mm10_refflat_BCD range=chr1:3234567-4545678...
tgtgcacactacacatgactagtatgtgcacactacacatgactagta
.
.
.
.
.
so on
... (2 Replies)
I have a fastq file from small RNA sequencing with sequence lengths between 15 - 30. I wanted to filter sequence lengths between 21-25 and write to another fastq file. how can i do that? (4 Replies)
I have a text file, input.fasta contains some protein sequences. input.fasta is shown below.
>P02649
MKVLWAALLVTFLAGCQAKVEQAVETEPEPELRQQTEWQSGQRWELALGRFWDYLRWVQT
LSEQVQEELLSSQVTQELRALMDETMKELKAYKSELEEQLTPVAEETRARLSKELQAAQA
RLGADMEDVCGRLVQYRGEVQAMLGQSTEELRVRLASHLRKLRKRLLRDADDLQKRLAVY... (8 Replies)
I sat down yesterday to write this script and have just realised that my methodology is broken........
In essense I have.....
----------------------------------------------------------------- (This line really is in the file)
Service ID: 12345 ... (7 Replies)
Discussion started by: Bashingaway
7 Replies
LEARN ABOUT SUSE
posix_fallocate
POSIX_FALLOCATE(3) Linux Programmer's Manual POSIX_FALLOCATE(3)NAME
posix_fallocate - allocate file space
SYNOPSIS
#define _XOPEN_SOURCE 600
#include <fcntl.h>
int posix_fallocate(int fd, off_t offset, off_t len);
DESCRIPTION
The function posix_fallocate() ensures that disk space is allocated for the file referred to by the descriptor fd for the bytes in the
range starting at offset and continuing for len bytes. After a successful call to posix_fallocate(), subsequent writes to bytes in the
specified range are guaranteed not to fail because of lack of disk space.
If the size of the file is less than offset+len, then the file is increased to this size; otherwise the file size is left unchanged.
RETURN VALUE
posix_fallocate() returns zero on success, or an error number on failure. Note that errno is not set.
ERRORS
EBADF fd is not a valid file descriptor, or is not opened for writing.
EFBIG offset+len exceeds the maximum file size.
EINVAL offset was less than 0, or len was less than or equal to 0.
ENODEV fd does not refer to a regular file.
ENOSPC There is not enough space left on the device containing the file referred to by fd.
ESPIPE fd refers to a pipe of file descriptor.
VERSIONS
posix_fallocate() is available since glibc 2.1.94.
CONFORMING TO
POSIX.1-2001.
POSIX.1-2008 says that an implementation shall give the EINVAL error if len was 0, or offset was less than 0. POSIX.1-2001 says that an
implementation shall give the EINVAL error if len is less than 0, or offset was less than 0, and may give the error if len equals zero.
SEE ALSO fallocate(2), lseek(2), posix_fadvise(2), feature_test_macros(7)COLOPHON
This page is part of release 3.25 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/.
GNU 2009-09-30 POSIX_FALLOCATE(3)