trouble understanding file option and command line arguments
Hi,
I am creating a program with the C language that simulates the WC command in Unix. My program needs to count lines, bytes and words. I have not added the code to count bytes and words yet. I am having trouble understanding what the file option/flag '-' does. I can not visualize how it moves through program code. argc and argv look at one line at a time and they only look at what is on the command line. I am not sure how a program is broken up into files for WC to read.
this is the code I have so far:
Right now I have code to just count the lines. I am testing the program on a hello world program below:
when I test the program, I get 0 for line count.
California State University, Northridge, USA, Prof Gabrovsky, Comp 322
Couple of questions as I try to decipher someones code who left...
What would something coded like this do?
IFS=:
grep FIELD1 /Path/Path2/Param.fle | read LBL1 LBL2 USRID EADR SUBJ SERVERNAME CFGTBL DIR
ERR=0
Param.fle contents..
FIELD1:FEI::FIELD2:dATAFIELD BATCH:MAIN SERVER......etc.. (2 Replies)
hi, can someone how to accept command line arguments as a variable using in script?
like: ./scriptname arguments
by accept arguments, I can use it in my script?
thx! (1 Reply)
Sometimes it works for me and sometimes I get this error:
syntax error on line 1, teletype
Basically I've got no idea whats going on, especially at the end of the command: bc
Any help is appreciated (1 Reply)
I have a C++ program. I read command line arguments, but if the value is not supplied, I default or make a calculation. Let's say I set it to a default value.
I can code this in several ways. Here I show three ways. What would be the best way for maintaining this code? The program will get very... (2 Replies)
What are the commands to manage ports from my command line.
Example:
Opening Ports, Closing Ports, Viewing their status, etc.
I am having a hard time finding this answer. I'm trying to trouble shoot some networking problems and it would be very helpful if I could just do this from the... (1 Reply)
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
1) The script is executed in the Korn shell.
2) Name the shell script file is asg6s.
3) The asg6s file is... (7 Replies)
:wall:killall -wHi
i need to understand how the -w option works in terms of processes.
If this command is issued does it literally terminate all running processes ..wait for them all to be terminated and then return to standard output ?
Thanks in advance (2 Replies)
I am looking for help in processing of those options: '-n' or '-p'
I understand what they do and how to use them.
But, I would like to use them with more than one file (and without any shell-loop; loading the 'perl' once.)
I did try it and -n works on 2 files.
Question is:
- is it possible to... (6 Replies)
Ok, thank you. Again I'm new to the programming thing, I'm just trying to figure out what exactly it is I need to do. How would I cash out bits? Numerous questions. I'm a dreamer. AI attempts to communicate with me regularly especially through unfinished apps that I'm assuming is my responsibility... (1 Reply)
Discussion started by: C-lo
1 Replies
LEARN ABOUT NETBSD
shuffle
SHUFFLE(1) BSD General Commands Manual SHUFFLE(1)NAME
shuffle -- print a random permutation of the command line arguments
SYNOPSIS
shuffle [-0] [-f filename ...] [-n number] [-p number] [arg] [...]
DESCRIPTION
The shuffle program prints a random permutation (or ``shuffle'') of its command line arguments. This can be useful in shell scripts for
selecting a random order in which to do a set of tasks, view a set of files, etc.
If the -f option is given, the data is taken from that files' contents or if the filename is - ``stdin''.
If the -n option is given, its argument is treated as a number, and the program prints a random permutation of the numbers greater than or
equal to 0 and less than the argument.
If the -p option is given, its argument is treated as a number, and the program prints that number of randomly selected lines or arguments in
a random order.
The -0 option changes the field separator character from
to , so that the output is suitable to be sent to xargs(1) (to handle filenames
with whitespace in them).
EXAMPLES
$ shuffle a b c d
c
b
d
a
$ shuffle -p 1 a b c d
d
$ shuffle -n 4 -p 2
0
3
SEE ALSO jot(1), random(6)HISTORY
The shuffle program first appeared in NetBSD 1.4.
AUTHORS
Written by Perry E. Metzger <perry@piermont.com>.
BSD February 18, 2009 BSD