10 More Discussions You Might Find Interesting
1. UNIX for Beginners Questions & Answers
Hello,
I'm new to scripting and I need to write a bash script. Here is example of file on which I'm working:
0.3092381 0.3262799 0.3425480 0.3578379 0.3719490
0.3846908 0.3958855 0.4053738 0.4130160 0.4186991
0.4223357 ... (1 Reply)
Discussion started by: jeo_fb
1 Replies
2. Shell Programming and Scripting
Hello!
I need help :) I have a file like this:
AA BC FG
RF TT GH
DD FF HH
(a few number of rows and three columns) and I want to put the letters of each column in a variable step by step in order to give them as input in another script. So I would like to obtain:
for the 1° loop:... (11 Replies)
Discussion started by: edekP
11 Replies
3. Shell Programming and Scripting
All,
I require a script that grabs some text from the gitHub API and will grep (or other function) for a string a characters that starts with (") quotes followed by two letters, may contain a pipe |, and ending with ) . What i have so far is below but it's not returning anything.
... (4 Replies)
Discussion started by: ChocoTaco
4 Replies
4. Windows & DOS: Issues & Discussions
so...
Lets assume I have a text file.
The text file contains multiple "#" symbols.
I want to replace all thos "#"s with a STRING using DOS/Batch
I want to add a certain TEXT to the end of each line.
How can I do this WITHOUT aid of sed, grep or anything linux related ? (1 Reply)
Discussion started by: pasc
1 Replies
5. Shell Programming and Scripting
I want to add/append the info in the following format to my.txt file.
20130702|abcd20130702.txt FN|SN|DOB
I tried the below script but it throws me some exceptions.
<#!/bin/sh
dt = date '+%y%m%d'members;
echo $dt+|+members+$dt;
/usr/bin/awk -f
BEGIN { FS="|"; OFS="|"; } { print... (6 Replies)
Discussion started by: harik1982
6 Replies
6. Shell Programming and Scripting
hello,
i have publicly available txt file with little less than 300000 rows. i want to extract from column 1 to column 218 and save it in another text file. i use the cut command but the file is saved with multiple rows from the source file onto a single row in the destination. basically it is... (6 Replies)
Discussion started by: madrazzii
6 Replies
7. Shell Programming and Scripting
This is appending a column.
My question is fairly simple. I have a program generating data in a form like so:
1 20
2 22
3 23
4 12
5 43
For ever iteration I'm generating this data. I have the basic idea with cut -f 2 fileA.txt | paste -d >> FileB.txt ???? I want FileB.txt to grow, and... (4 Replies)
Discussion started by: theawknewbie
4 Replies
8. UNIX for Dummies Questions & Answers
I need to extract all the p-value numbers and the rho numbers from a .txt file and write them as coma separated values in a new file. Ideally I would get two files in the end, one for p- values and one for rho. Any suggestions? I appreciate your help!!!
The .txt file looks essentially like this... (5 Replies)
Discussion started by: eggali
5 Replies
9. Shell Programming and Scripting
I have data as follow in the txt file.
I want to skip line starting with '#' sign.
#command program
abc defmt
exp refmt
... ...
I want to store abc exp .... in a array.
I want to store defmt refmt in a array
I need command to read each line in the file.
I need... (6 Replies)
Discussion started by: ekb
6 Replies
10. UNIX for Dummies Questions & Answers
Hi,
I have already read a lot of posts on sending attachments in unix...but none of them were of help for my problem...so here goes..
i wanna attach a text file and send to a mail id..used the following code :
uuencode "$File1" "$File1" ;|mail -s "$Mail_sub" abc@abc.com
it works... (2 Replies)
Discussion started by: ash22
2 Replies
COUNTER(9) BSD Kernel Developer's Manual COUNTER(9)
NAME
counter -- SMP-friendly kernel counter implementation
SYNOPSIS
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/counter.h>
counter_u64_t
counter_u64_alloc(int wait);
void
counter_u64_free(counter_u64_t c);
void
counter_u64_add(counter_u64_t c, int64_t v);
void
counter_enter();
void
counter_exit();
void
counter_u64_add_protected(counter_u64_t c, int64_t v);
uint64_t
counter_u64_fetch(counter_u64_t c);
void
counter_u64_zero(counter_u64_t c);
#include <sys/sysctl.h>
SYSCTL_COUNTER_U64(parent, nbr, name, access, ptr, descr);
SYSCTL_ADD_COUNTER_U64(ctx, parent, nbr, name, access, ptr, descr);
DESCRIPTION
counter is a generic facility to create counters that can be utilized for any purpose (such as collecting statistical data). A counter is
guaranteed to be lossless when several kernel threads do simultaneous updates. However, counter does not block the calling thread, also no
atomic(9) operations are used for the update, therefore the counters can be used in any non-interrupt context. Moreover, counter has special
optimisations for SMP environments, making counter update faster than simple arithmetic on the global variable. Thus counter is considered
suitable for accounting in the performance-critical code pathes.
counter_u64_alloc(wait)
Allocate a new 64-bit unsigned counter. The wait argument is the malloc(9) wait flag, should be either M_NOWAIT or M_WAITOK. If
M_NOWAIT is specified the operation may fail.
counter_u64_free(c)
Free the previously allocated counter c.
counter_u64_add(c, v)
Add v to c. The KPI does not guarantee any protection from wraparound.
counter_enter()
Enter mode that would allow to safely update several counters via counter_u64_add_protected(). On some machines this expands to
critical(9) section, while on other is a nop. See IMPLEMENTATION DETAILS.
counter_exit()
Exit mode for updating several counters.
counter_u64_add_protected(c, v)
Same as counter_u64_add(), but should be preceded by counter_enter().
counter_u64_fetch(c)
Take a snapshot of counter c. The data obtained is not guaranteed to reflect the real cumulative value for any moment.
counter_u64_zero(c)
Clear the counter c and set it to zero.
SYSCTL_COUNTER_U64(parent, nbr, name, access, ptr, descr)
Declare a static sysctl oid that would represent a counter. The ptr argument should be a pointer to allocated counter_u64_t. A read
of the oid returns value obtained through counter_u64_fetch(). Any write to the oid zeroes it.
SYSCTL_ADD_COUNTER_U64(ctx, parent, nbr, name, access, ptr, descr)
Create a sysctl oid that would represent a counter. The ptr argument should be a pointer to allocated counter_u64_t. A read of the
oid returns value obtained through counter_u64_fetch(). Any write to the oid zeroes it.
IMPLEMENTATION DETAILS
On all architectures counter is implemented using per-CPU data fields that are specially aligned in memory, to avoid inter-CPU bus traffic
due to shared use of the variables between CPUs. These are allocated using UMA_ZONE_PCPU uma(9) zone. The update operation only touches the
field that is private to current CPU. Fetch operation loops through all per-CPU fields and obtains a snapshot sum of all fields.
On amd64 a counter update is implemented as a single instruction without lock semantics, operating on the private data for the current CPU,
which is safe against preemption and interrupts.
On i386 architecture, when machine supports the cmpxchg8 instruction, this instruction is used. The multi-instruction sequence provides the
same guarantees as the amd64 single-instruction implementation.
On some architectures updating a counter require a critical(9) section.
SEE ALSO
atomic(9), critical(9), locking(9), malloc(9), sysctl(9), uma(9)
HISTORY
The counter facility first appeared in FreeBSD 10.0.
AUTHORS
The counter facility was written by Gleb Smirnoff and Konstantin Belousov.
BSD
February 7, 2014 BSD