I have a project where I have to use bzcat to uncompress a file and use that output as the data to run another program on.
I understand that you would do (bzcat filename.bz2 ! program name) but then how do you access that data in the c program??? Please help thanks (2 Replies)
Does anyone know how to answer this? I have tried many different commands, I just cant get it right.....
Search the file 'data' for all of the lines that contain the pattern 'unx122'
and put those lines in the file 'matches'. (2 Replies)
I've got a very ugly pipeline for analyzing web server logs (but nevermind the application; I've come across this in other scripts as well). I want to nicely comment the steps in the pipeline, but I can't seem to do it.
I know, for instance that in csh/sh/bash, a # begins a comment, and any... (2 Replies)
I am trying to ftp a file to a Unix server that contains null values. The file is on a Unisys system. It contains null values between data but when I look at the file on the Unix server, the nulls are gone and the data is compressed together. How do I not lose those null values?
TIA,
Betty (1 Reply)
I need to read input from a file, and make sure nothing prints after column 72.
basically, ignore input after character 72 until the next newline character.
Any help is appreciated. I have been searching forever! (10 Replies)
Hello gurus - I must be missing something, or there is a better way - pls enlighten me
I'm on a Solaris 10 vm running the following pipeline to reduce some apache logs (actually lynx dumps of /server-status/ when threads are above a threshold) to a set of offending DDoS IP addresses.
awk... (10 Replies)
use strict;
use warnings;
open (my $fhConditions, "<input1.txt"); #open input file1
open (my $fhConditions1, "<input2.txt");#open input file2
open (my $w1, ">output1");
open (my $w2, ">output2");
our $l = 10;#set a length to be searched for match
our $site="AAGCTT";#pattern to be matched... (1 Reply)
Hello All,
I need to convert a csv file to pipeline delimiter file in UNIX. The data in file itself contains comma with double qouted qualifier apart from the comma separator. Let me know how to do it. Appreciate any help if awk can be used to do it.
Mentioned below is the sample record of... (14 Replies)
Hi
Can anybody please explain me the following script in detail
Value=`echo "if ( ${FACTOR} >= 1 ) {1}" | bc`
What does "{1}" mean to here ? (3 Replies)
Hello,
I am attempting to ssh to a server and run a set of commands on a remote set of servers. I am getting the following error below, I am thinking quotes may be the problem. This command works on the local machine in bash. Not when I ssh to a remote server. Basically the command should... (3 Replies)
Discussion started by: jaysunn
3 Replies
LEARN ABOUT V7
expr
EXPR(1) General Commands Manual EXPR(1)NAME
expr - evaluate arguments as an expression
SYNOPSIS
expr arg ...
DESCRIPTION
The arguments are taken as an expression. After evaluation, the result is written on the standard output. Each token of the expression is
a separate argument.
The operators and keywords are listed below. The list is in order of increasing precedence, with equal precedence operators grouped.
expr | expr
yields the first expr if it is neither null nor `0', otherwise yields the second expr.
expr & expr
yields the first expr if neither expr is null or `0', otherwise yields `0'.
expr relop expr
where relop is one of < <= = != >= >, yields `1' if the indicated comparison is true, `0' if false. The comparison is numeric if
both expr are integers, otherwise lexicographic.
expr + expr
expr - expr
addition or subtraction of the arguments.
expr * expr
expr / expr
expr % expr
multiplication, division, or remainder of the arguments.
expr : expr
The matching operator compares the string first argument with the regular expression second argument; regular expression syntax is
the same as that of ed(1). The (...) pattern symbols can be used to select a portion of the first argument. Otherwise, the
matching operator yields the number of characters matched (`0' on failure).
( expr )
parentheses for grouping.
Examples:
To add 1 to the Shell variable a:
a=`expr $a + 1`
To find the filename part (least significant part) of the pathname stored in variable a, which may or may not contain `/':
expr $a : '.*/(.*)' '|' $a
Note the quoted Shell metacharacters.
SEE ALSO ed(1), sh(1), test(1)DIAGNOSTICS
Expr returns the following exit codes:
0 if the expression is neither null nor `0',
1 if the expression is null or `0',
2 for invalid expressions.
EXPR(1)