To cfajohnson. I did not expect this response from you who I recognise as an expert in shell syntax. The O/P script did not contain the problem, my initial response did not contain the problem, but the example was designed to teach.
Please explain the error message in my example in your own words.
I was not commenting on any error message. I was answering the question, "Can you briefly explain the curly brackets."
# sub: find block (in cols), return line-numbers (begin-end) or 0 if notfound
sub findb{
my ($exp1,$col1,$exp2,$col2)= @_; # $exp = expression to find, $col - column to search in
my $cnt=0;
my ($val1,$val2);
my ($beg,$end);
for($cnt=1;$cnt<=65536;$cnt++){
$val1 =... (3 Replies)
Hi Gurus:
I am trying to understand the following line of code.I did enough of googling to understand but no luck.Please help me understand the follow chunk of code:
X=$0
MOD=${X%/*}/env.ksh
X is the current script from which I am trying to execute.
Say if X=test.ksh
$MOD is echoing :... (3 Replies)
Hi
I have a questions related 2 commands : 'du' and 'ls'.
Why is the difference between output of 'du' and 'ls' cmd's ?
Command 'du' :
------------------
jakubn@server1 /home/jakubn $ du -s *
4 engine.ksh
1331 scripts
'du -s *' ---> shows block count size on disk (512 Bytes... (5 Replies)
Hi all
I stuck with a problem. I want to understand the execution of the below code. Can any one please help me
`sqlplus username/passwd@DB << EOF
set serveroutput on
declare
begin
sql_query;
end;
/
commit
/
quit
EOF`
My ques is why do we use EOF and how does it help. (4 Replies)
Hi,
Please help me to understand the bold segments in the below regex.
Both are of same type whose meaning I am looking for.
find . \( -iregex './\{6,10\}./src' \) -type d -maxdepth 2
Output:
./20111210.0/src
In continuation to above:
sed -e 's|./\(*.\{1,3\}\).*|\1|g'
Output: ... (4 Replies)
Hi Guys,
I am new to scripting , I am trying to rebuild a script based on an old script. Can someone help me figure out what the script is doing? This is only a part of the script.
I am looking to interpret these two points in the scripts:-
1)
test=`echo $?`
while
I do not... (3 Replies)
Hi, I saw the following explanation about alias in bash from gnu website, but I didn't get the meaning:
Bash always reads at least one complete line of input before executing any of the commands on that line.
Aliases are expanded when a command is read, not when it is executed. Therefore, an... (3 Replies)
I tried to use lseek system call to determine the number of bytes in a file. To do so, I used open system call with O_APPEND flag to open a file. As lseek returns the current offset so I called lseek for opened file with offset as zero and whence as SEEK_CUR. So I guess it must return the number of... (3 Replies)
Hi,
I found this in a script and I would like to know how this works
Code is here:
# var1=PART1_PART2
# var2=${var1##*_}
# echo $var2
PART2
I'm wondering how ##* makes the Shell to understand to pick up the last value from the given. (2 Replies)
Discussion started by: sathyaonnuix
2 Replies
LEARN ABOUT DEBIAN
combine
COMBINE(1)COMBINE(1)NAME
combine - combine sets of lines from two files using boolean operations
SYNOPSIS
combine file1 and file2
combine file1 not file2
combine file1 or file2
combine file1 xor file2
_ file1 and file2 _
_ file1 not file2 _
_ file1 or file2 _
_ file1 xor file2 _
DESCRIPTION
combine combines the lines in two files. Depending on the boolean operation specified, the contents will be combined in different ways:
and Outputs lines that are in file1 if they are also present in file2.
not Outputs lines that are in file1 but not in file2.
or Outputs lines that are in file1 or file2.
xor Outputs lines that are in either file1 or file2, but not in both files.
"-" can be specified for either file to read stdin for that file.
The input files need not be sorted, and the lines are output in the order they occur in file1 (followed by the order they occur in file2
for the two "or" operations). Bear in mind that this means that the operations are not commutative; "a and b" will not necessarily be the
same as "b and a". To obtain commutative behavior sort and uniq the result.
Note that this program can be installed as "_" to allow for the syntactic sugar shown in the latter half of the synopsis (similar to the
test/[ command). It is not currently installed as "_" by default, but you can alias it to that if you like.
SEE ALSO join(1)AUTHOR
Copyright 2006 by Joey Hess <joey@kitenet.net>
Licensed under the GNU GPL.
moreutils 2012-04-09 COMBINE(1)