Hi ,
I have a question about performance of writing into a file.
Will it take more time to open a file, write a line into the file and close the file
if the file size grows bigger and bigger??
Say, I have two files of sizes 100KB and 20MB.
Will it take more time to open/write a... (1 Reply)
About 4 years ago I wrote this tool inspired by Rob Urban's collect tool for DEC's Tru64 Unix. What makes this tool as different as collect was in its day is its ability to run at a low overhead and collect tons of stuff. I've expanded the general concept and even include data not available in... (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 all,
I was able to do a script to gather a few files and sort them.
here it is:
#!/usr/bin/ksh
ls *mainFile* |cut -c20-21 | sort > temp
set -A line_array
i=0
file_name='temp'
while read file_line
do
line_array=${file_line}
let i=${i}+1 (5 Replies)
Hello,
I'm running a script on AIX to process lines in a file. I need to enclose the second column in quotation marks and write each line to a new file. I've come up with the following:
#!/bin/ksh
filename=$1
exec >> $filename.new
cat $filename | while read LINE
do
echo $LINE | awk... (2 Replies)
Hello Gurus,
We are facing some performance issue in UNIX. If someone had faced such kind of issue in past please provide your suggestions on this .
Problem Definition:
/Few of load processes of our Finance Application are facing issue in UNIX when they uses a shell script having below... (19 Replies)
Hi guys,
what is the relation between I/O performance and file systems.
I have a file systems called /dcs/data01 which is having 4Tb size.
According our application we can split the file system like
dcs/data01 -> 1Tb
dcs/data02 -> 1Tb
dcs/data03 -> 1Tb
dcs/data04 -> 1Tb
do you... (4 Replies)
Please, I need help tuning my script. It works but it's too slow.
The code reads an acivity log file with 50.000 - 100.000 lines and filters error messages from it. The data in the actlog file look similar to this:
02/08/2011 00:25:01,ANR2034E QUERY MOUNT: No match found using this criteria.... (5 Replies)
Hello all -
I am to this forum and fairly new in learning unix and finding some difficulty in preparing a small shell script. I am trying to make script to sort all the files given by user as input (either the exact full name of the file or say the files matching the criteria like all files... (3 Replies)
Hi Experts,
I have a filelist collected from another server , now want to sort the output using date/time stamp filed.
- Filed 6, 7,8 are showing the date/time/stamp.
Here is the input:
#----------------------------------------------------------------------
-rw------- 1 root ... (3 Replies)
Discussion started by: rveri
3 Replies
LEARN ABOUT MINIX
join
JOIN(1) General Commands Manual JOIN(1)NAME
join - relational database operator
SYNOPSIS
join [-an] [-e s] [-o list] [-tc] file1 file2
DESCRIPTION
Join forms, on the standard output, a join of the two relations specified by the lines of file1 and file2. If file1 is `-', the standard
input is used.
File1 and file2 must be sorted in increasing ASCII collating sequence on the fields on which they are to be joined, normally the first in
each line.
There is one line in the output for each pair of lines in file1 and file2 that have identical join fields. The output line normally con-
sists of the common field, then the rest of the line from file1, then the rest of the line from file2.
Fields are normally separated by blank, tab or newline. In this case, multiple separators count as one, and leading separators are dis-
carded.
These options are recognized:
-an In addition to the normal output, produce a line for each unpairable line in file n, where n is 1 or 2.
-e s Replace empty output fields by string s.
-o list
Each output line comprises the fields specified in list, each element of which has the form n.m, where n is a file number and m is a
field number.
-tc Use character c as a separator (tab character). Every appearance of c in a line is significant.
SEE ALSO sort(1), comm(1), awk(1).
BUGS
With default field separation, the collating sequence is that of sort -b; with -t, the sequence is that of a plain sort.
The conventions of join, sort, comm, uniq, look and awk(1) are wildly incongruous.
7th Edition April 29, 1985 JOIN(1)