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 MINIX
pipe
PIPE(2) System Calls Manual PIPE(2)NAME
pipe - create an interprocess communication channel
SYNOPSIS
#include <unistd.h>
int pipe(int fildes[2])
DESCRIPTION
The pipe system call creates an I/O mechanism called a pipe. The file descriptors returned can be used in read and write operations. 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] will pick up the data.
PIPE_MAX equals 7168 under Minix, but note that most systems use 4096.
It is assumed that after the pipe has been set up, two (or more) cooperating processes (created by subsequent fork calls) will pass data
through the pipe with read and write calls.
The shell has a syntax to set up a linear array of processes connected by pipes.
Read calls on an empty pipe (no buffered data) with only one end (all write file descriptors closed) returns an end-of-file.
The signal SIGPIPE is generated if a write on a pipe with only one end is attempted.
RETURN VALUE
The function value zero is returned if the pipe was created; -1 if an error occurred.
ERRORS
The pipe call will fail if:
[EMFILE] Too many descriptors are active.
[ENFILE] The system file table is full.
[ENOSPC] The pipe file system (usually the root file system) has no free inodes.
[EFAULT] The fildes buffer is in an invalid area of the process's address space.
SEE ALSO sh(1), read(2), write(2), fork(2).
NOTES
Writes may return ENOSPC errors if no pipe data can be buffered, because the pipe file system is full.
BUGS
Should more than PIPE_MAX bytes be necessary in any pipe among a loop of processes, deadlock will occur.
4th Berkeley Distribution August 26, 1985 PIPE(2)