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"
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)
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)
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)
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)
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)
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
LEARN ABOUT SUSE
arithmetic
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