Replace r with the record number to be extracted:
For modern AWK's which support RS regular expressions:
If portability is a factor, use the first suggestion.
Hi All,
I am having trouble through, I am reading the input from tab delimited file containing several records,
e.g.
line1 field1 field2 field3 so on..
line2 field1 field2 field3 so on..
..
..
on the basis of certain fields for each record in input file, I have to retrieve... (1 Reply)
Hi,
I have a sample data file that contains name-value pairs in it.
For example:
name1=value1
name2=value2
name3=value3
...
...
...
My concern is
1. How to get values of name1, name2, name3 using korn shell script?
2. I don't want to access each varible using $name1,$name2, $name3... (2 Replies)
There is one Text file data.txt.
Data within this file looks like:
a.sql
b.sql
c.sql
d.sql
.....
.....
want to write a shell script which will access these values within a loop, access one value at a time and store into a variable. can anyone plz help me. (2 Replies)
Hi, I am writting some perl scripts for daily backup process. In which I want to pass some data/referance from another txt file. Text file contains only one column and multiple rows. I want to pass this data to variables of another perl script.
e.g.
Refdoc.txt file contains data as:
perl1... (3 Replies)
Hi,
I have below type of data in a text file in unix.
Emp_Name Emp_Dept
Raj 101
Amruta 100
Shilpa 100
Rohit 123
Amol 198
Rosh 101
Gaurav 198
Number of employees can be even more.
Need a command or a... (2 Replies)
I have a requirement to read the xml file and split the files into two diffrent files in Unix shell script. Could anyone please help me out with this requirement.
Sample file
---------------
0,<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Information... (3 Replies)
I need some help with this code below, i doesnt know why it will run twice with my function, but my function only got if else, any other way that can read line and put into array?
while read line; do
read -A array <<<$line
n=${#array}
for ((i=1;i<$n;i++)); do
print... (1 Reply)
Hi everyone,
I am trying to write a bash script which reads a data file and does some algebraic operations.
here is the structure of data.xml file that I have;
1 <data>
2 .
3 .
4 .
5 </data>
6 <data>
7 .
8 .
9 .
10</data>
etc.
Each data block contains same number of lines (say... (4 Replies)
I have a process that requires me to read data from huge log files and find the most recent entry on a per-user basis. The number of users may fluctuate wildly month to month, so I can't code for it with names or a set number of variables to capture the data, and the files are large so I don't... (7 Replies)
Discussion started by: rbatte1
7 Replies
LEARN ABOUT ULTRIX
pipe
pipe(2) System Calls Manual pipe(2)Name
pipe - create an interprocess channel
Syntax
include <limits.h> /*Definition of PIPE_MAX*/
pipe(fildes)
int fildes[2];
Arguments
fildes Passing an address as an array of two integers into the system call.
Description
The system call creates an I/O mechanism called a pipe. The file descriptors returned can be used in and operations. Their integer values
will be the two lowest available at the time of the function call. The O_NONBLOCK and FD_CLOEXEC flags will be clear on both file descrip-
tors.
When the pipe is written using the descriptor fildes[1], up to PIPE_MAX bytes of data are buffered before the writing process is suspended.
A read using the descriptor fildes[0] picks up the data.
It is assumed that after the pipe has been set up, two (or more) cooperating processes (created by subsequent calls) pass data through the
pipe with and calls.
The shell has a syntax to set up a linear array of processes connected by pipes.
For further information on how and calls behave with pipes, see the and reference pages.
A signal is generated if a write on a pipe with only one end is attempted.
Restrictions
Should more than 4096 bytes be necessary in any pipe among a loop of processes, deadlock may occur.
The underlying implementation of pipes is no longer socket based, but rather implemented through the file system. Any application that
needs socket functionality from pipes should use the system call.
Return Values
The function value zero is returned if the pipe was created; -1 if an error occurred.
Diagnostics
The call fails if:
[EMFILE] Too many descriptors are active.
[ENFILE] The system file table is full.
[EFAULT] The fildes buffer is in an invalid area of the process's address space.
Environment
Differs from the System V definition in that ENFILE is not a possible error condition.
See Alsosh(1), fork(2), read(2), socketpair(2), write(2)pipe(2)