The 'if ' better (I believe ti was desighned for that usage) to use in that way:
The if acting on return code from command ('grep' here) - (return in shell could be checked by '$?' right after execution a command.)
The '&>/dev/null' part redirect any returns or/and error infor into nowhere, as the result is not interesting here, but only return code
Hi,
I have a statement in shell script which i am writing below:
if ]
then
.....
What is the meaning of -a option in files, meaning of the statement in the if condition ] means.
Thanks (3 Replies)
can someone please tell me what is wrong with the below. i'm trying to get a script to run if the content of a variable is either small letter y or capital letter Y.
if
then
whatever
fi (4 Replies)
I want to write a program that would convert yard to feet and feet to yard.
i.e
1 yard = 3 * feet
Echo "enter a"
read a
expr a *3
The trick is that I want to give the user some options. After the conversion from yard to feet is done, I want to ask the user whether or not he/she wants to... (10 Replies)
In my ksh script, if the conditions of a if statement are true, then do nothing; otherwise, execute some commands.
How do I write the "do nothing" statement in the following example?
Example:
if (( "$x"="1" && "$y"="a" && "$z"="happy" ))
then
do nothing
else
command
command
fi... (3 Replies)
Hi All,
I am using Unix ksh script.
I need to insert values to a table using the o/p from a slelect statement.
Can anybody Help!
My script looks like tihs.
---`sqlplus -s username/password@SID << EOF
set heading off
set feedback off
set pages 0
insert into ${TB_NAME}_D... (2 Replies)
I have the program:
#!/bin/ksh
echo Please enter yes or no
read n
typeset -l n
if ]
then
echo My name
exit
else
echo delete my name
fi
Question:
How can I make the program accept only the word "yes" or "no" otherwise it will ask the user to re-enter?
Thanks! (7 Replies)
I'm trying to create a script that would allow me to identify the sucessful removal of a file. Here's what i put together so far, let me know if it's correct or not.
FILE_NAME="cactus.dat"
FILE_FIND='find / -name $FILE_NAME'
if ;then
echo "cactus.dat was not removed successfully" ... (3 Replies)
Hi,
I have this code here. Its suppose to do something when certain condition is met, I'm pretty sure at least one of the condition will be meet somewhere in the loop but it always go to else part of the script.
Is something wrong on this script?
age_list=`tar -tvf /home/dir/$tarfile... (4 Replies)
Hi folks,
I have a scenario to convert the update statements into insert statements using shell script (awk, sed...) or in database using regex.
I have a bunch of update statements with all columns in a file which I need to convert into insert statements.
UPDATE TABLE_A SET COL1=1 WHERE... (0 Replies)
Discussion started by: dev123
0 Replies
LEARN ABOUT PLAN9
grep
GREP(1) General Commands Manual GREP(1)NAME
grep - search a file for a pattern
SYNOPSIS
grep [ option ... ] pattern [ file ... ]
DESCRIPTION
Grep searches the input files (standard input default) for lines (with newlines excluded) that match the pattern, a regular expression as
defined in regexp(6). Normally, each line matching the pattern is `selected', and each selected line is copied to the standard output.
The options are
-c Print only a count of matching lines.
-h Do not print file name tags (headers) with output lines.
-i Ignore alphabetic case distinctions. The implementation folds into lower case all letters in the pattern and input before interpre-
tation. Matched lines are printed in their original form.
-l (ell) Print the names of files with selected lines; don't print the lines.
-L Print the names of files with no selected lines; the converse of -l.
-n Mark each printed line with its line number counted in its file.
-s Produce no output, but return status.
-v Reverse: print lines that do not match the pattern.
Output lines are tagged by file name when there is more than one input file. (To force this tagging, include /dev/null as a file name
argument.)
Care should be taken when using the shell metacharacters $*[^|()= and newline in pattern; it is safest to enclose the entire expression in
single quotes '...'.
SOURCE
/sys/src/cmd/grep.c
SEE ALSO ed(1), awk(1), sed(1), sam(1), regexp(6)DIAGNOSTICS
Exit status is null if any lines are selected, or non-null when no lines are selected or an error occurs.
GREP(1)