How can i create a regular expression which can detect a new line charcter followed by a special character say * and replace these both by a string of zero length?
Eg:
Input File san.txt
hello
hi ... (6 Replies)
how to find for a file whose name has all characters in uppercase after 'project'?
I tried this:
find . -name 'project**.pdf'
./projectABC.pdf
./projectABC123.pdf
I want only ./projectABC.pdf
What is the regular expression that correponds to "all characters are capital"?
thanks (8 Replies)
Hi,
below is a piece of code written by my predecessor at work.
I'm kind of a newbie and am trying to figure out all the regular expressions in this piece of code.
It is really a tough time for me to figure out all the regular expressions.
Please shed some light on the regular expressions... (3 Replies)
Hi,
In ksh, I am trying to compare folder names having -141- in it's name.
e.g.: 4567-141-8098 should match this expression '*-141-*'
but, -141-2354 should fail when compared with '*-141-*'
simlarly, abc should fail when compared with '*-141-*'
I tried multiple things but nevertheless,... (5 Replies)
what elements does " /^/ " match?
I did the test which indicates that it matches single lowercase character like 'a','b' etc. and '1','2' etc.
But I really confused with that. Because, "/^abc/" matches strings like "abcedf" or "abcddddee".
So, what does caret ^ really mean?
Any response... (2 Replies)
I have a file that I'm trying to find all the cases of phone number extensions and deleting them. So input file looks like:
abc
x93825
def
13234
x52673
hello
output looks like:
abc
def
13234
hello
Basically delete lines that have 5 numbers following "x". I tried: x\(4) but it... (7 Replies)
I am new to shell scripts.Can u please help me on this req.
test_user = "Arun"
if
echo "test_user is a word"
else
echo "test_user is not a word" (1 Reply)
Hi
Ilove unix and alwyas trying to to learn unix,but i am weak in using regular expressions.can you please give me a littel brief discription that how can i understand them and how to use .your response could lead a great hand in my unix love. (1 Reply)
Discussion started by: manoj attri
1 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)