Hi,
I have a program that runs two threads in stead of two processes. I want to use pipe to redirect the output of the first thread to the input of the second thread.
One thread is continuously writing to a pipe, and the other thread will read from the pipe.
How do I do that?
Is there... (2 Replies)
I know how to read and write if i have a forked process with only one child. However what is involved with reading and writing with many forked processes. Say one parent that forks 5 children, and needs to communicate with all 5 in half duplex.
int temp, counter=0;
do{
pipe(temp);
... (5 Replies)
Hi,
I will use below command for grep single string ("osuser" is search string)
ex: find . -type f | xarg grep -il osuser
but i have one more string "v$session"
here i want to grep in which file these two strings are present.
any help is appreciated,
Thanks in advance.
Gagan (2 Replies)
Hi,
I have a requirement with,
No~Dt~Notes
1~2011/08/1~"aaa
bbb
ccc
ddd
eee
fff
ggg
hhh"
Single column alone got splitted into multiple lines.
I require the output as
No~Dt~Notes
1~2011/08/1~"aaa<>bbb<>ccc<>ddd<>eee<>fff<>ggg<>hhh"
mean to say those new lines to be... (1 Reply)
Hi,
I am trying to convert multiple Unix pipe symbol or bar into single |. I have tried with the following sed statements, but, no success :(. I need it using sed only
echo "sed 's/\|\+/\|/g'
sed 's/*/\|/'
sed 's/\|*/|/'
sed -r 's/\|+/\|/'
However, the below awk code is working fine.... (4 Replies)
I have a script that finds all sffs and extracts them into .fastq file types. What I need to do is change the .fastq to .fasta using the below script. How can I change the input.fastq and output.fasta to mirror the file's name? Would I use an array and use the default iterator?
#!/bin/bash
... (3 Replies)
Single command to ls all the files inside a particular directory hierachy and output this to a file and open this in a vim file so that i can use gf command in vim to browse through all the files inside this hierachy.
eg :
dir1/dir2
and
dir1/dir3
dir2 and dir3 contain the files i need... (7 Replies)
The task I have to do is something along the lines "I receive some input and based on the first character I send it through pipe to one of the children to print".
The scheme it is based on is 1->2; 1->3; 1->4; 2 will print all the input that starts with a letter, 3 will print all the input that... (2 Replies)
Discussion started by: Ildiko
2 Replies
LEARN ABOUT V7
pipe
PIPE(2) System Calls Manual PIPE(2)NAME
pipe - create an interprocess channel
SYNOPSIS
pipe(fildes)
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 4096 bytes of data are buffered before the writing process is suspended. A read
using the descriptor fildes[0] will pick up the data. Writes with a count of 4096 bytes or less are atomic; no other process can inter-
sperse data.
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.
SEE ALSO sh(1), read(2), write(2), fork(2)DIAGNOSTICS
The function value zero is returned if the pipe was created; -1 if too many files are already open. A signal is generated if a write on a
pipe with only one end is attempted.
BUGS
Should more than 4096 bytes be necessary in any pipe among a loop of processes, deadlock will occur.
ASSEMBLER
(pipe = 42.)
sys pipe
(read file descriptor in r0)
(write file descriptor in r1)
PIPE(2)