04-01-2008
are you looking for something like:
if [ -e $filename] then
...
this will check if the file exists.
9 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
i have got a file where the env command is appended 5 times. i have to now look for the username and display it in the form of
1) PWD=/home/lee.ballancore
2) USER=lee.ballancore
3) MAIL=/var/spool/mail/lee.ballancore
4) LOGNAME=lee.ballancore
5) HOME=/home/lee.ballancore
6)... (1 Reply)
Discussion started by: nehaquick
1 Replies
2. Shell Programming and Scripting
I have a for loop in my script as shown below.
for file_path in $file_list ; do
........my code
..........
......
done
Can i restrict the number of files parsing to the variable file_path as 50?
That is, even if I have some 100 files in file_list, I need to take only 50 files for... (7 Replies)
Discussion started by: Vijay06
7 Replies
3. Shell Programming and Scripting
Hi,
I am facing issues with test condition. I had a compound condition to write for both if and while,
In one of the texts i referred, with a korn shell we can write compound statements like: ], however this doesn't worked for me. For example:
if ] doesn't works, but
if || worked.
... (1 Reply)
Discussion started by: amritps
1 Replies
4. Shell Programming and Scripting
Hello
I want to compare values of two variables as CHECK condition in a while loop.
eg:
var1=0
var2=10
while
do
echo " $var1 "
var1=`expr $var1 + 1`
done
However this is giving error.How to do it in a proper manner?
Thanks. (3 Replies)
Discussion started by: dashing201
3 Replies
5. Shell Programming and Scripting
I'm a complete UNIX newbie trying to write a simple shell script. The pseudo-code for the part I'm having trouble with is as such:
read something
while ; do this
The loop terminates at EOF (like when Ctrl+D is pushed) and displays the number of lines the user entered (kept in the loop as a... (17 Replies)
Discussion started by: Sovereign110
17 Replies
6. Shell Programming and Scripting
Gurus,
I need to read a line from a file and strip the characters from it and compare the stripped value with the value I pass to the script while executing it. Below is the code for the same. But when i execute the code, it is throwing an error.
#!/bin/ksh
. /home/.i_env
... (14 Replies)
Discussion started by: svajhala
14 Replies
7. Shell Programming and Scripting
Hi,
Could you please tell what is the meaning of -z in while loop condition.
For example,
while ; do
echo "*** Enter the age "
readage (3 Replies)
Discussion started by: vidyaj
3 Replies
8. Shell Programming and Scripting
hello,
I would like to do exit at the end ie list all errors before exiting
How to put the token exit in a variable with a loop ?
Thanks
function g1 () {
case "$1" in
(-0-0 | -0-1 | -0-2 | -0-3 | -1-0 | -1-1 | -1-2 | -1-3)
# nothing, OK !
;;
(*)
echo 'Fatal, $1 = '"'$1'"', Date... (9 Replies)
Discussion started by: amazigh42
9 Replies
9. Shell Programming and Scripting
Hi,
I was trying to write a shell script which reads csv file and sends mail in html format along with tables. Hope i have completed 1st part , but while sending mail i was trying to highlight some rows in the table based on the egrep outcome. If the string exists in line/INPUT, i am trying to... (4 Replies)
Discussion started by: varmas424
4 Replies
while(n) Tcl Built-In Commands while(n)
__________________________________________________________________________________________________________________________________________________
NAME
while - Execute script repeatedly as long as a condition is met
SYNOPSIS
while test body
_________________________________________________________________
DESCRIPTION
The while command evaluates test as an expression (in the same way that expr evaluates its argument). The value of the expression must a
proper boolean value; if it is a true value then body is executed by passing it to the Tcl interpreter. Once body has been executed then
test is evaluated again, and the process repeats until eventually test evaluates to a false boolean value. Continue commands may be exe-
cuted inside body to terminate the current iteration of the loop, and break commands may be executed inside body to cause immediate termi-
nation of the while command. The while command always returns an empty string.
Note: test should almost always be enclosed in braces. If not, variable substitutions will be made before the while command starts execut-
ing, which means that variable changes made by the loop body will not be considered in the expression. This is likely to result in an
infinite loop. If test is enclosed in braces, variable substitutions are delayed until the expression is evaluated (before each loop iter-
ation), so changes in the variables will be visible. For an example, try the following script with and without the braces around $x<10:
set x 0
while {$x<10} {
puts "x is $x"
incr x
}
SEE ALSO
break(n), continue(n), for(n), foreach(n)
KEYWORDS
boolean value, loop, test, while
Tcl while(n)