You should lookup regular expressions. The ^ character matches "beginning of line". The square brackets define a character class. Basically, it means, "match any character in the square brackets". The ^ character has a special meaning inside the character class only if it's the 1st character in the character class. It means NOT.
So this means " find any line that starts with anything except a '#' character, and replace that character with a '#' character ".
The parentheses "capture" a regular expression match. In vi, they must be escaped so that vi knows you want to capture, instead of trying to match the parentheses. The \1 notation in the replacement string means replace with the 1st "captured" match.
Can anyone tell me what is the purpose of a substitute variable in the unix programming language and give an example where it may be used?
Thanks! (0 Replies)
hi!
first i want to apologize for two things. my English and (possible) posting in the wrong sub forum (i couldn't find one that fits my question)
I am needing a script that can substitute rm.
the idea is that the operator can/must delete some folders and files from time to time, when the free... (2 Replies)
i'm writing a script that will extract and substitute a certain part of a data.
i'm having trouble with the substituting part ...
Here's my data looks like:
01/01/08-001-23:46:18-01/01/08-23:50:43
01/01/08-003-23:45:19-01/01/08-23:55:49
01/01/08-005-23:52:18-01/01/08-23:58:52
i want to... (6 Replies)
Hi,
I have query terms like this:
a) apple bannana
b) apple bannana AND chickko
c) "milk shake" OR Graphes orange
whereever there is space substitue with AND operator.
I tried like this: (2 Replies)
correct file names are:
*_0.txt
*_1.txt
incorrect file names are:
*_12.txt
*_0123.txt
*_04321.txt
all files that are incorrect need to replace the ending with *_1.txt
therefore need to create a loop to find the wrong files in a dir ->that dont end in _1.txt or _0.txt and then... (3 Replies)
My question is how would I substitute for ceratain number of occurences in a line? If this is my input
rjohns BFSTDBS01 Standard Silver NPRO30DINCR 2 Client
Is it possible to change the first 3 occurences of space " " to a comma? (7 Replies)
I usually use :
Code:
awk '{gsub(/xxx/,"yyy");print}'
to substitute xxx with yyy.
I have a problem substitute an expression like
Code:
x ' y
Because of the ( ' )
Any idea on how to get over this problem?
Thanks (2 Replies)
Hi there,
i am updating a file on UNIX and have many lines as per below :
listen:x:37:4:Network Admin:/usr/net/nls:
i would like to substitute from the :/usr to the end of the line.
so at the moment im using this :
:s/"\/$/ /g
but i get an error.can anyone help?
thank you (3 Replies)
I have to parse ASCII files, output the relevant data to a comma-delimited file and load it into a database table.
The specs for the file format have been recently updated and one section is causing problems. This is the original layout for that section.
... (2 Replies)
Hello All,
I have a shell script where with the lines below:
echo "${v_sd_dateTime},${RUN_QUEUE_SIZE},${LOAD_AVERAGE},${v_sd_load_list},${v_sd_thread_count_list}" >> ${v_sd_file}
Format of the output :
01/05/2005 08:00:00, RUN_QUEUE_SIZE, LOAD_AVG, CPU_PROD1, CPU_PROD2, THREADS_PROD1,... (1 Reply)
Discussion started by: Supriya_84
1 Replies
LEARN ABOUT SUSE
match
MATCH(1L) Schily's USER COMMANDS MATCH(1L)NAME
match - searches for patterns in files
SYNOPSIS
match [ -option ] pattern [ file ... ]
DESCRIPTION
Match searches the named files or standard input (if no filenames are given) for the occurrences of the given pattern on each line. The
program accepts literal characters or special pattern matching characters. All lines that match the pattern are output on standard output.
You can only specify one pattern string for each match, however, you can construct an arbitrarily complex string. When you do not specify
a file, match can be used as a filter to display desired lines. Standard in is used if no files are specified.
OPTIONS -not, -v
Prints all lines that do not match.
-i Ignore the case of letters
-m Force not to use the magic mode
-w Search for pattern as a word
-x Display only those lines which match exactly
-c Display matching count for each file
-l Display name of each file which matches
-s Be silent indicate match in exit code
-h Do not display filenames
-n Precede matching lines with line number (with respect to the input file)
-b Precede matching lines with block number
REGULAR EXPRESSIONS
The following is a table of all the pattern matching characters:
c An ordinary character (not one of the special characters discussed below) is a one character regular expression that matches that
character.
c A backslash () followed by any special character is a one character regular expression that matches the special character itself.
The special characters are:
! # % * { } [ ] ? ^ $
! Logical OR as in match this!that!the_other. You may have to use `{}' for precedence grouping.
# A hash mark followed by any regular expression matches any number (including zero) occurrences of the regular expression.
? Matches exactly any one character. W? matches Wa, Wb, Wc, W1, W2, W3 ...
* Matches any number of any character.
% Matches exactly nothing. It can be used in groups of ored patterns to specify that an empty alternative is possible.
{} Curly brackets may be used to enclose patterns to specify a precedence grouping, and may be nested. {%!{test}}version matches the
strings testversion and version.
[string]
A non empty string of characters enclosed in square brackets is a one character regular expression that matches any one character in
that string. If however the first character of the string is a circumflex (^), the one character expression matches any character
which is not in the string. The ^ has this special meaning only if it occurs first in the string. The minus (-) may be used to indi-
cate a range of consecutive ASCII characters; for example, [0-9] is equivalent to any one of the digits. The - loses it's special
meaning if it occurs first (after an initial ^, if any) or last in the string. The right square bracket (]) and the backslash ()
must be quoted with a backslash if you want to use it within the string.
^ Matches the beginning of a line.
$ Matches the end of a line. (^*$ matches any entire line)
EXAMPLES FILES
None.
SEE ALSO grep(1), fgrep(1), egrep(1)DIAGNOSTICS NOTES
Even if a match occurs more than once per line, the line is output only once.
Quote special pattern matching characters to prevent them from being expanded by the Command Interpreter.
BUGS
The length of the pattern is currently limited to 100 characters.
This limit is reduced by 38 if the -w option is used.
Joerg Schilling 15. Juli 1988 MATCH(1L)