Hello All,
I am brand new to the UNIX world and so far and very intrigued and enjoy scripting. This is just a new language for me. I would really like assistance with the below request. Any help would be greatly appreciated!
I want to create a flat file in Vi that has a header field and... (0 Replies)
Hi All
I am reading a huge file of size 2GB atleast. I am reading each line and cutting certain columns and writing it to another file.
Here is the logic.
int main()
{
string u_line;
string Char_List;
string u_file;
int line_pos;
string temp_form_u_file;
... (10 Replies)
Hi!
Thank you for the help yesterday
This is the finished product
There is one more thing I would like to do to it but I’m not to certain
On how to proceed I would like to log all output to a log in order to
Be able to roll back
This script is meant to be used in repairing a... (4 Replies)
can anyone help to share the knowledge on linux os improvement?
1) os account
- use window AD authentication, such as ldap, but how to set /etc/passwd, where to put user home?
2) user account activity
- how to log os user activity
share the idea and what tools can do that...thx (5 Replies)
Heyas
I've been working on my project TUI (Text User Interface) for quite some time now, its a hobby project, so nothing i sit in front of 8hrs/day.
Since the only 'real' programming language i knw is Visual Basic, based upon early steps with MS-Batch files. When i 'joined' linux 3 years ago,... (7 Replies)
Hello Coders
Some time ago i was asking about python and bash performances, and i was told i could post the regarding code, and someone would kindly help to make it faster (if possible).
If you have noted, i'm on the way to finalize, finish, stable TUI - Text(ual) User Interface.
It is a... (6 Replies)
Below script is used to search numeric data from around 400 files in a folder. I have 300 such folders. Need help in performance improvement in the script.
Below Script searches 20 such folders ( 300 files in each folder) simultaneously. This increases cpu utilization upto 90% What changes... (3 Replies)
Hi,
another little question...
"sn" is an array whose elements can vary from about 55,000 to about 150,000 elements. Each element consists of an integer between 0-255, eg: ${sn} contain the value: 103 . For a decrypt-procedure I need scroll all the elements 4 or 5 times. Here is an example of... (15 Replies)
Hi guys and gals...
MacBook Pro.
OSX 10.13.2, default bash terminal.
I have a flat file 1920 bytes in size of whitespaces only. I need to put every single whitespace character into a bash array cell.
Below are two methods that work, but both are seriously ugly.
The first one requires that I... (7 Replies)
Hello,
For several of our scripts we are using awk to search patterns in files with data from other files. This works almost perfectly except that it takes ages to run on larger files. I am wondering if there is a way to speed up this process or have something else that is quicker with the... (15 Replies)
Discussion started by: SDohmen
15 Replies
LEARN ABOUT OPENDARWIN
fork
FORK(2) BSD System Calls Manual FORK(2)NAME
fork -- create a new process
SYNOPSIS
#include <sys/types.h>
#include <unistd.h>
pid_t
fork(void);
DESCRIPTION
Fork() causes creation of a new process. The new process (child process) is an exact copy of the calling process (parent process) except for
the following:
o The child process has a unique process ID.
o The child process has a different parent process ID (i.e., the process ID of the parent process).
o The child process has its own copy of the parent's descriptors. These descriptors reference the same underlying objects, so that,
for instance, file pointers in file objects are shared between the child and the parent, so that an lseek(2) on a descriptor in the
child process can affect a subsequent read or write by the parent. This descriptor copying is also used by the shell to establish
standard input and output for newly created processes as well as to set up pipes.
o The child processes resource utilizations are set to 0; see setrlimit(2).
RETURN VALUES
Upon successful completion, fork() returns a value of 0 to the child process and returns the process ID of the child process to the parent
process. Otherwise, a value of -1 is returned to the parent process, no child process is created, and the global variable errno is set to
indicate the error.
ERRORS
Fork() will fail and no child process will be created if:
[EAGAIN] The system-imposed limit on the total number of processes under execution would be exceeded. This limit is configuration-
dependent.
[EAGAIN] The system-imposed limit MAXUPRC (<sys/param.h>) on the total number of processes under execution by a single user would
be exceeded.
[ENOMEM] There is insufficient swap space for the new process.
SEE ALSO execve(2), wait(2)HISTORY
A fork() function call appeared in Version 6 AT&T UNIX.
4th Berkeley Distribution June 4, 1993 4th Berkeley Distribution