I am taking a class in UNIX and have written a script that needs to countdown from a number that is read in from the keyboard to zero. If no number is given the start of the countdown should default to 10.
I can't get this to do the default
#! /bin/sh
echo Enter a number here to countdown... (2 Replies)
I am looking for a way to display on a single line, a running countdown for a given amount of time in a terminal using a bash script.
I am looking for this to use as part of a larger bash script that captures Video. The script sets up a bunch of parameters for DVgrab, and one of the parameters... (11 Replies)
Hi guys, I've found two nifty little scripts on these forums one which detects if the F5 key has been pressed:
#/bin/sh
_key()
{
local kp
ESC=$'\e'
_KEY=
read -d '' -sn1 _KEY
case $_KEY in
"$ESC")
while read -d '' -sn1 -t1 kp
do
_KEY=$_KEY$kp
... (0 Replies)
Hi all,
Does anyone know of any FUN countdown script that I can use for my script? At the moment, am just using sleep 10 or more and then print stuff into the screen to allow more time for the user to decide whether they want to continue running the script or abort?
Just thought of wanting... (3 Replies)
Hello, I have another problem with my script - I would like to have a countdown timer visible on the screen, and at the same time, I want te be able to do something else. And when the time runs out, I need to know about that inside the script somehow and do some action. I guess that would require 2... (3 Replies)
In the below bash when the perl is it possible to hide the commands from running on screen and display a process countdown?
For example, on the cygwin screen now the user sees each process in the command running as running protocol refGene, running protocol popfreq_all, etc... Could a... (0 Replies)
Hello. I am pretty new to unix and shell scripting and I was wondering if there might be a way to banner a countdown timer inside a script. We currently have an existing script that does a 2 minute sleep but thought it might be fun to actually make it banner a countdown timer until it is finished.... (3 Replies)
Discussion started by: thumbelina
3 Replies
LEARN ABOUT DEBIAN
plan9-test
TEST(1) General Commands Manual TEST(1)NAME
test - set status according to condition
SYNOPSIS
test expr
DESCRIPTION
Test evaluates the expression expr. If the value is true the exit status is null; otherwise the exit status is non-null. If there are no
arguments the exit status is non-null.
The following primitives are used to construct expr.
-r file True if the file exists (is accessible) and is readable.
-w file True if the file exists and is writable.
-x file True if the file exists and has execute permission.
-e file True if the file exists.
-f file True if the file exists and is a plain file.
-d file True if the file exists and is a directory.
-s file True if the file exists and has a size greater than zero.
-t fildes True if the open file whose file descriptor number is fildes (1 by default) is the same file as /dev/cons.
-A file True if the file exists and is append-only.
-L file True if the file exists and is exclusive-use.
-Tfile True if the file exists and is temporary.
s1 = s2 True if the strings s1 and s2 are identical.
s1 != s2 True if the strings s1 and s2 are not identical.
s1 True if s1 is not the null string. (Deprecated.)
-n s1 True if the length of string s1 is non-zero.
-z s1 True if the length of string s1 is zero.
n1 -eq n2 True if the integers n1 and n2 are arithmetically equal. Any of the comparisons -ne, -gt, -ge, -lt, or -le may be used in place
of -eq. The (nonstandard) construct -l string, meaning the length of string, may be used in place of an integer.
a -nt b True if file a is newer than (modified after) file b.
a -ot b True if file a is older than (modified before) file b.
f -older t True if file f is older than (modified before) time t. If t is a integer followed by the letters y(years), M(months), d(days),
h(hours), m(minutes), or s(seconds), it represents current time minus the specified time. If there is no letter, it represents
seconds since epoch. You can also concatenate mixed units. For example, 3d12h means three days and twelve hours ago.
These primaries may be combined with the following operators:
! unary negation operator
-o binary or operator
-a binary and operator; higher precedence than -o
( expr ) parentheses for grouping.
The primitives -b, -u, -g, and -s return false; they are recognized for compatibility with POSIX.
Notice that all the operators and flags are separate arguments to test. Notice also that parentheses and equal signs are meaningful to rc
and must be enclosed in quotes.
EXAMPLES
Test is a dubious way to check for specific character strings: it uses a process to do what an rc(1) match or switch statement can do. The
first example is not only inefficient but wrong, because test understands the purported string "-c" as an option.
if (test $1 '=' "-c") echo OK # wrong!
A better way is
if (~ $1 -c) echo OK
Test whether is in the current directory.
test -f abc -o -d abc
SOURCE
/src/cmd/test.c
SEE ALSO rc(1)TEST(1)