Sponsored Content
Full Discussion: RS232 programming problem
Top Forums UNIX for Advanced & Expert Users RS232 programming problem Post 302246680 by otheus on Tuesday 14th of October 2008 05:56:32 AM
Old 10-14-2008
1. You should start the READ process first.

2. When you do the read, you're trying to read 500 bytes. It never gets to 500. So I'm not sure how your program outputs what it does. If you want, you can read 1 byte at a time and collect the input into a string which you output after it's 20 bytes long or so. Otherwise, use poll().
 

10 More Discussions You Might Find Interesting

1. Programming

RS232 communication optimisation

Need help for RS232 communication with switches in order to optimise the data traffic. How to manipulate different flags in termios struct to do the same? (1 Reply)
Discussion started by: ManishSaxena
1 Replies

2. UNIX for Advanced & Expert Users

VNC via Rs232

Hi ! Is there somebody who is able to connect a VNC session via serial cable ? There is a hint on the VNC homepage that it is possible to configure that. But how? thanks joerg (2 Replies)
Discussion started by: joerg
2 Replies

3. Solaris

rs232 pci-card

hello mates, do you know a manufactor for rs232 serial pci cards for the sparc architecture? it seems that there is no original product from sun for that purpose. strange, isn't it? problem is that i have a V250 with only one db9 rs232 serial port, and i need it for a modem connection, but i also... (1 Reply)
Discussion started by: pressy
1 Replies

4. Programming

Using non standard baudrate 28800 with rs232

Hi, can somebody help me with this one? I have to configure rs232 write/read inside a C program. I'm using the termios.h (POSIX) The problem is that the only baudrate that works for me is 28800 and it is not supported any more from this driver. :( So I can't write : cfsetispeed(&options,... (4 Replies)
Discussion started by: palexo
4 Replies

5. AIX

Transferring files via RS232 cable

Current setup: Some old AIX standalone machine (F series) My WinXP laptop Null modem cable from laptop to AIX machine (console port). On Hypterminal on WinXP I can connect to the AIX machine (serial connection), but when I try to transfer file, it will just sit there. I'm guessing the... (3 Replies)
Discussion started by: apra143
3 Replies

6. Programming

How to read the CTS and DSR of RS232 in Unix using C language?

Hello to all Gurus out there, Could you show me a source code in Unix platform using C language. I want to read the status or voltage level of the DSR and CTS. Thanks a lot, Swing5 (2 Replies)
Discussion started by: Swing5
2 Replies

7. Shell Programming and Scripting

Problem with awk programming

i want to calculate power of 10 as follows: coef=2.0588 ra1=$(awk 'BEGIN{print 10^$coef}') it gives a result 1 when, if i calculate ra1=$(awk 'BEGIN{print 10^2.0588}') it gives a result 114.499 what should i do? (2 Replies)
Discussion started by: SANGUINE
2 Replies

8. UNIX for Dummies Questions & Answers

Can A File Be Copied to an RS232 Port on Unix?

We have a text/csv file (4mb) sitting on a Unix box. The PC belongs to a retail store and they're asking me to bring the file over to Windows so they can import the file. Can a file be copied to an rs232 port? If so how? The idea is that I'll hook up a null modem cable to the Unix com port,... (2 Replies)
Discussion started by: alivebyscience
2 Replies

9. Programming

Programming problem

Hi Everybody. I have an Ubuntu linux 10.04 os and want be able to use the website of intuit but it only runs on unix. Is there any way that I can put the needed drivers in this os since both linux/unix share some distinctive programs. If this is not possible how can I save the information that I... (1 Reply)
Discussion started by: mk631219
1 Replies

10. UNIX for Dummies Questions & Answers

Connecting PIC16F877A using Easypic5 via RS232 with Linux

I searched the forums for RS232 issues, but all of the results don't help me solving my problem, so I had to open new thread. This is the problem: I have PIC16F877A micro-controller and I'm programming it with Easypic5(the PIC programming device(board) from MikroElektronika) and I want to... (1 Reply)
Discussion started by: ivan_vasileski
1 Replies
TAIL(1) 						    BSD General Commands Manual 						   TAIL(1)

NAME
tail -- display the last part of a file SYNOPSIS
tail [-F | -f | -r] [-q] [-b number | -c number | -n number] [file ...] DESCRIPTION
The tail utility displays the contents of file or, by default, its standard input, to the standard output. The display begins at a byte, line or 512-byte block location in the input. Numbers having a leading plus ('+') sign are relative to the beginning of the input, for example, ``-c +2'' starts the display at the second byte of the input. Numbers having a leading minus ('-') sign or no explicit sign are relative to the end of the input, for example, ``-n 2'' displays the last two lines of the input. The default start- ing location is ``-n 10'', or the last 10 lines of the input. The options are as follows: -b number The location is number 512-byte blocks. -c number The location is number bytes. -f The -f option causes tail to not stop when end of file is reached, but rather to wait for additional data to be appended to the input. The -f option is ignored if the standard input is a pipe, but not if it is a FIFO. -F The -F option implies the -f option, but tail will also check to see if the file being followed has been renamed or rotated. The file is closed and reopened when tail detects that the filename being read from has a new inode number. If the file being followed does not (yet) exist or if it is removed, tail will keep looking and will display the file from the begin- ning if and when it is created. The -F option is the same as the -f option if reading from standard input rather than a file. -n number The location is number lines. -q Suppresses printing of headers when multiple files are being examined. -r The -r option causes the input to be displayed in reverse order, by line. Additionally, this option changes the meaning of the -b, -c and -n options. When the -r option is specified, these options specify the number of bytes, lines or 512-byte blocks to display, instead of the bytes, lines or blocks from the beginning or end of the input from which to begin the display. The default for the -r option is to display all of the input. If more than a single file is specified, each file is preceded by a header consisting of the string ``==> XXX <=='' where XXX is the name of the file unless -q flag is specified. EXIT STATUS
The tail utility exits 0 on success, and >0 if an error occurs. EXAMPLES
To display the last 500 lines of the file foo: $ tail -n 500 foo Keep /var/log/messages open, displaying to the standard output anything appended to the file: $ tail -f /var/log/messages SEE ALSO
cat(1), head(1), sed(1) STANDARDS
The tail utility is expected to be a superset of the IEEE Std 1003.2-1992 (``POSIX.2'') specification. In particular, the -F, -b and -r options are extensions to that standard. The historic command line syntax of tail is supported by this implementation. The only difference between this implementation and historic versions of tail, once the command line syntax translation has been done, is that the -b, -c and -n options modify the -r option, i.e., ``-r -c 4'' displays the last 4 characters of the last line of the input, while the historic tail (using the historic syntax ``-4cr'') would ignore the -c option and display the last 4 lines of the input. HISTORY
A tail command appeared in PWB UNIX. BSD
March 16, 2013 BSD
All times are GMT -4. The time now is 07:15 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy