Visit Our UNIX and Linux User Community

Top Forums Shell Programming and Scripting What can i do to check that the input is all alphabet.. ? Post 14107 by Jimbo on Monday 28th of January 2002 11:18:31 AM
Old 01-28-2002
expr "$answer" : "[A-Za-z]*$"

Above command will return non-zero (length of answer) if it consists of only upper/lower letters. To restrict it to only lowercase or only uppercase, just remove A-Z or a-z. As coded, does not allow for spaces in answer.

You can either capture the output in a variable, then test the variable, or you can nest the above command directly within an if-statement.
Jimbo
 
Test Your Knowledge in Computers #175
Difficulty: Medium
ENIAC was one of the first electronic computers and occupied 167 square meters, weighed 27 tons and consumed 150kW of electricity.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Check on Input

HI all, I would like to know how the user can be restricted for entering only the number and not characters in sheel scripts.. Suppose code is like this echo 'Enter the number' read Value Now user may enter 'a' as value... But i want to disallow him for entering characters other than... (3 Replies)
Discussion started by: dhananjaysk
3 Replies

2. UNIX for Dummies Questions & Answers

check the input

how to check whether a given input is a number or a string? (1 Reply)
Discussion started by: Shilpi
1 Replies

3. Shell Programming and Scripting

To check if the first character is a alphabet or number

Hi, I need to find whether the first character in a line is a alphabet or a number. If its a number i should sort it numerically. If its a alphabet i should sort it based on the ASCII value.And if it is something other than alphabet or number then sort it based on ASCII value. The code i used... (2 Replies)
Discussion started by: ragavhere
2 Replies

4. UNIX for Dummies Questions & Answers

checking wether an input is using letters of the alphabet

afternoon forums. I need to get a way of testing as to wether an inputed character is part of the english alphabet. i have come up with the following code but its not working at all. until '] do echo This is not a Letter done any help would be beneficial to me. (1 Reply)
Discussion started by: strasner
1 Replies

5. Programming

How to check an input variable

Suppose we have a simple situation, like the following C++ instructions: int x; cout << "Insert x: "; cin >> x; while ( x-- < 0 ) ; Of course, if it is written something different from an integer, the while loop shall not end. So, how can we check if the input x is of the right type? (2 Replies)
Discussion started by: Luke Bonham
2 Replies

6. Shell Programming and Scripting

Check input parameter

Hi all i need to check that if user has passed any input parameter while executing he shell script like ./test1.sh -a"-v" then do smothing if user execute the script without giving input paramater then ./test1.sh then do something how can we check this input parameter (6 Replies)
Discussion started by: aishsimplesweet
6 Replies

7. Shell Programming and Scripting

Input file check

Hi, I have a script which runs daily. It gets 3 input files test1,test2,test3. I want to do a validation in my script to make sure i have all the 3 files available before running. If any one of the file is missing i want to break the script. Could you please help me with this request. ... (1 Reply)
Discussion started by: Krrishv
1 Replies

8. Shell Programming and Scripting

To Check whether the Input is a Year or Not?

Hi Guys I have a Requirement that the input will be given and i have to check whether the input is a Year or not. For Example 2004,2009 and so on forth will be considered a year and anything else like 12:15 or else will not be. Have built the below Code set -x echo " Enter... (6 Replies)
Discussion started by: Ajesh
6 Replies

9. Shell Programming and Scripting

Check user input

Hi, I need my script to check if the user enters 3 values if not 5 values to my script and alert if the input has any other number of values. for example: ./myscript.sh 22 56 3221 - > correct ./myscript.sh 22 56 3221 45 777 -> correct ./myscript.sh 22 56 3221 45 -> incorrect Please... (6 Replies)
Discussion started by: mohtashims
6 Replies

10. UNIX for Dummies Questions & Answers

Check Column corresponding to input

I have a file which extracts data from an HTML file For Eg HTML file contains: New York;ABC;145;Yes;YES;No New York;BCD;113;Yes;YES;No New York;NAS;63;Yes;YES;No ------------------------ London-48;CBT;16;Yes;YES;No London-48;CME;17;Yes;YES;No London-48;EUR;52;Yes;YES;No... (7 Replies)
Discussion started by: newkid.7955
7 Replies
RRDp(3) 						User Contributed Perl Documentation						   RRDp(3)

NAME
RRDp - Attach RRDtool from within a perl script via a set of pipes; SYNOPSIS
use RRDp RRDp::start path to RRDtool executable RRDp::cmd rrdtool commandline $answer = RRD::read $status = RRD::end $RRDp::user, $RRDp::sys, $RRDp::real, $RRDp::error_mode, $RRDp::error DESCRIPTION
With this module you can safely communicate with the RRDtool. After every RRDp::cmd you have to issue an RRDp::read command to get RRDtools answer to your command. The answer is returned as a pointer, in order to speed things up. If the last command did not return any data, RRDp::read will return an undefined variable. If you import the PERFORMANCE variables into your namespace, you can access RRDtool's internal performance measurements. use RRDp Load the RRDp::pipe module. RRDp::start path to RRDtool executable start RRDtool. The argument must be the path to the RRDtool executable RRDp::cmd rrdtool commandline pass commands on to RRDtool. Check the RRDtool documentation for more info on the RRDtool commands. Note: Due to design limitations, RRDp::cmd does not support the "graph -" command - use "graphv -" instead. $answer = RRDp::read read RRDtool's response to your command. Note that the $answer variable will only contain a pointer to the returned data. The reason for this is, that RRDtool can potentially return quite excessive amounts of data and we don't want to copy this around in memory. So when you want to access the contents of $answer you have to use $$answer which dereferences the variable. $status = RRDp::end terminates RRDtool and returns RRDtool's status ... $RRDp::user, $RRDp::sys, $RRDp::real these variables will contain totals of the user time, system time and real time as seen by RRDtool. User time is the time RRDtool is running, System time is the time spend in system calls and real time is the total time RRDtool has been running. The difference between user + system and real is the time spent waiting for things like the hard disk and new input from the Perl script. $RRDp::error_mode and $RRDp::error If you set the variable $RRDp::error_mode to the value 'catch' before you run RRDp::read a potential ERROR message will not cause the program to abort but will be returned in this variable. If no error occurs the variable will be empty. $RRDp::error_mode = 'catch'; RRDp::cmd qw(info file.rrd); print $RRDp::error if $RRDp::error; EXAMPLE
use RRDp; RRDp::start "/usr/local/bin/rrdtool"; RRDp::cmd qw(create demo.rrd --step 100 DS:in:GAUGE:100:U:U RRA:AVERAGE:0.5:1:10); $answer = RRDp::read; print $$answer; ($usertime,$systemtime,$realtime) = ($RRDp::user,$RRDp::sys,$RRDp::real); SEE ALSO
For more information on how to use RRDtool, check the manpages. AUTHOR
Tobias Oetiker <tobi@oetiker.ch> perl v5.16.3 2014-06-10 RRDp(3)

Featured Tech Videos

All times are GMT -4. The time now is 04:21 PM.
Unix & Linux Forums Content Copyright 1993-2020. All Rights Reserved.
Privacy Policy