Sponsored Content
Full Discussion: stack problem
Top Forums UNIX for Dummies Questions & Answers stack problem Post 18714 by Jimbo on Tuesday 2nd of April 2002 09:53:45 AM
Old 04-02-2002
Quote:
I understand this will return the final character of the $file variable.
Just to be clear, we are talking about returning the first or final character of a file, and does not matter if it is referenced by actual name or the filename is contained in a variable. Returning portions of what is currently held in a variable is very common, but I think not what we want here.

OK, so head -1 myfile gets you the first line. Now pipe that into a command that will cut the first column out. But if the first line is empty, this solution results in null:
Code:
char1=`head -1 myfile | cut -c1`
echo "first character is $char1"

Jimbo
 

7 More Discussions You Might Find Interesting

1. Programming

memory stack problem

Hi, I am writing a C program under SCO Unix. I have a memory stack problem but do not know how to go about fixing it. I have tried running INSURE but that does not detect any problems. Essentially the problem is that the memory address shifts on return from a routine. I pass a pointer to... (3 Replies)
Discussion started by: jkeagy
3 Replies

2. Programming

stack query

can anyone explain how the local variables are acessed from a stack frame of that particular function..since stacks can only push or pop values and stack pointer always points to top of the stack and the frame pointer always points to the end of the previous stack frame..how local variables are... (4 Replies)
Discussion started by: aloksave
4 Replies

3. Programming

what is stack winding and stack unwinding

helo can u tell me what do you mean by stack winding and stack unwinding Regards, Amit (2 Replies)
Discussion started by: amitpansuria
2 Replies

4. HP-UX

Problem with stack overflow

Hi, I get a problem with stack overflow on HP-UX, when running a C program. Pid 28737 received a SIGSEGV for stack growth failure. Possible causes: insufficient memory or swap space, or stack size exceeded maxssiz. The possible cause i found, was that the definition of a structure had... (0 Replies)
Discussion started by: karthikb23
0 Replies

5. UNIX for Dummies Questions & Answers

Kernel Stack vs User Mode Stack

Hi, I am new to the linux kernel development area. I want to know what is the difference between kernel mode stack and user mode stack? Does each process has a user mode stack and a kernel mode stack?? Or Each process has a user mode stack and there is only one kernel mode stack that is shared by... (4 Replies)
Discussion started by: saurabhkoar
4 Replies

6. Shell Programming and Scripting

Stack Trace

Hi All Thought it would be kind of fun to implement a stack trace for a shell script that calls functions within a sub shell. This is for bash under Linux and probably not portable - #! /bin/bash error_exit() { echo "=======================" echo $1 echo... (4 Replies)
Discussion started by: steadyonabix
4 Replies

7. UNIX for Dummies Questions & Answers

What happens to the stack?

Consider this bad code, edited in Windows and run via CygWin after dos2unix so be aware of any hidden "\r" charatcers... #!/bin/bash n=0 stackit() { eval $1 if then exit 0 fi n=$ echo "$n" stackit stackit } stackit stackit Run under CygWin:- AMIGA:~> cd /tmp AMIGA:/tmp>... (2 Replies)
Discussion started by: wisecracker
2 Replies
ARITHMETIC(6)							 BSD Games Manual						     ARITHMETIC(6)

NAME
arithmetic -- quiz on simple arithmetic SYNOPSIS
arithmetic [-o +-x/] [-r range] DESCRIPTION
arithmetic asks you to solve problems in simple arithmetic. Each question must be answered correctly before going on to the next. After every 20 problems, it prints the score so far and the time taken. You can quit at any time by typing the interrupt or end-of-file character. The options are as follows: -o By default, arithmetic asks questions on addition of numbers from 0 to 10, and corresponding subtraction. By supplying one or more of the characters +-x/, you can ask for problems in addition, subtraction, multiplication, and division, respectively. If you give one of these characters more than once, that kind of problem will be asked correspondingly more often. -r If a range is supplied, arithmetic selects the numbers in its problems in the following way. For addition and multiplication, the numbers to be added or multiplied are between 0 and range, inclusive. For subtraction and division, both the required result and the number to divide by or subtract will be between 0 and range. (Of course, arithmetic will not ask you to divide by 0.) The default is 10. When you get a problem wrong, arithmetic will remember the numbers involved, and will tend to select those numbers more often than others, in problems of the same sort. Eventually it will forgive and forget. arithmetic cannot be persuaded to tell you the right answer. You must work it out for yourself. DIAGNOSTICS
``What?'' if you get a question wrong. ``Right!'' if you get it right. ``Please type a number.'' if arithmetic doesn't understand what you typed. SEE ALSO
bc(1), dc(1) BSD
May 31, 1993 BSD
All times are GMT -4. The time now is 11:30 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy