I am facing a problem in replacing the file contents by iterating through the list.
My present code:
Code:
#!/bin/bash#
TFILE="/tmp/vinay/testb_1.txt"
while read linedo
aline="$line"
echo $aline
code=`echo $aline|cut -d ',' -f1`
country=`echo $aline|cut -d... (5 Replies)
hi all,
i am writing a ksh script, i am logging into an oracle db via sqlplus and running a select statement but i dont know how i can store the results from the sql so i can iterate over it and do more operations over it. I dont want to write a stored procedure with a cursor since i need to... (2 Replies)
Hey everyone.
Is it possible to use two arrays in a loop?
Basically what I am trying to do is iterate through the elements in an array, and, based on a condition, use the current position in the array to point to that index in the array. Here's the loop structure I'm looking for:
... (1 Reply)
Hello all,
I have a confusion with calloc function :
wz. the difference between the following 2 statemnts:
char *ptr;
char = (char*)calloc(num, sizeof(char));
char = (char*)calloc(num, sizeof(char*));
Am really confused!!!!!
---------- Post updated at 09:32 AM... (1 Reply)
Hello, I am working on a coding project for a class and to test the program I have created, I have come up with 100 different test cases. The program takes four text files as input, so each of the test cases is contained in a folder with four files.
I have a folder called 'tests', within which... (1 Reply)
Hi,
I've recently started using Awk commands as i need it to pull information out of a file and give me the mean value of a series of numbers. Here is the code i run on my Infile and it works just fine.
awk '{if ($1 == "Mam189") print $0}' Infile | awk '{if ($1 != $2) print $0}' | awk... (5 Replies)
Hi , experts.
I work on Linux station (RedHat 5.7), regular user, but have root password.
%> uname -a
Linux ran1log06 2.6.18-238.1.1.el5 #1 SMP Tue Jan 4 13:32:19 EST 2011 x86_64 x86_64 x86_64 GNU/Linux
%> cat /etc/issue
Red Hat Enterprise Linux Client release 5.7 (Tikanga)
Kernel \r on... (5 Replies)
I need to run the same awk function over an entire directly of files.
This is the awk:
awk '{$(NF+1)=1}1'
Is there a way that I can run this command once over all of the files, along the lines of:
awk '{$(NF+1)=1}1' *
so that I do not have to run this several times?
My main concern is... (2 Replies)
Hi,
I am trying to do something similar to the for loop example from KSH For Loop Array: Iterate Through Array Values
$: cat y.ksh
#!/bin/ksh
# set array called nameservers
set -A nameservers 192.168.1.1 192.168.1.5 202.54.1.5
# print all name servers
for i in ${nameservers}
do
... (3 Replies)
Discussion started by: newbie_01
3 Replies
LEARN ABOUT REDHAT
dup2
DUP(2) Linux Programmer's Manual DUP(2)NAME
dup, dup2 - duplicate a file descriptor
SYNOPSIS
#include <unistd.h>
int dup(int oldfd);
int dup2(int oldfd, int newfd);
DESCRIPTION
dup and dup2 create a copy of the file descriptor oldfd.
After successful return of dup or dup2, the old and new descriptors may be used interchangeably. They share locks, file position pointers
and flags; for example, if the file position is modified by using lseek on one of the descriptors, the position is also changed for the
other.
The two descriptors do not share the close-on-exec flag, however.
dup uses the lowest-numbered unused descriptor for the new descriptor.
dup2 makes newfd be the copy of oldfd, closing newfd first if necessary.
RETURN VALUE
dup and dup2 return the new descriptor, or -1 if an error occurred (in which case, errno is set appropriately).
ERRORS
EBADF oldfd isn't an open file descriptor, or newfd is out of the allowed range for file descriptors.
EMFILE The process already has the maximum number of file descriptors open and tried to open a new one.
WARNING
The error returned by dup2 is different to that returned by fcntl(..., F_DUPFD, ...) when newfd is out of range. On some systems dup2 also
sometimes returns EINVAL like F_DUPFD.
CONFORMING TO
SVr4, SVID, POSIX, X/OPEN, BSD 4.3. SVr4 documents additional EINTR and ENOLINK error conditions. POSIX.1 adds EINTR.
SEE ALSO fcntl(2), open(2), close(2)Linux 1.1.46 1994-08-21 DUP(2)