Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: ioctl : strace
Top Forums UNIX for Advanced & Expert Users ioctl : strace Post 302297008 by jim mcnamara on Thursday 12th of March 2009 10:03:46 AM
Old 03-12-2009
I don't understand your question. The programmer who wrote the code set the value of the request.

TCGETS requests a struct termios. It is part of SVR4, not POSIX. Since your process is opening a perl module, not a tty, this is not going to work. Files like a Select.pm - those files are not terminals.

If you wrote this: call isatty() first, if the return is true then
Code:
#include <termios.h>
...........
      struct termios original_opts
      int res=0;
      res=tcgetattr(fd, &original_opts);

Save the original_opts, copy to a new struct, then change the terminal settings you want, call tcsetattr with the new_opts struct, then when you are done, call tcsetattr with original_opts to set the term back the way it was. termios is the POSIX way to do this.

What the heck this code dump is showing I don't really know.
 

10 More Discussions You Might Find Interesting

1. Programming

ioctl()

UNIX, gnu cc compiler, SUN Ultra 60 Hello, this is my first post, so please bear with me. I'm currently developing a test environment for a network subsystem that, when live, accesses databases and other network elements. However, my test environment will be run offline, so I need to fake... (4 Replies)
Discussion started by: j_t_kim
4 Replies

2. UNIX for Dummies Questions & Answers

Inappropriate ioctl for device

Hello, I have a cron entry: 59 23 * * * . $HOME/.profile;mydate=`date '+%Y%m%d'`;mv filename filename_$mydate Which works fine interactively, but gives me the following error when it runs in cron: Your "cron" job on servername . $HOME/.profile;mydate=`date '+ produced the... (4 Replies)
Discussion started by: steelrose
4 Replies

3. UNIX for Advanced & Expert Users

help running strace

OK so I wanted to know how does grep outputs to the pipe and how sort reads from it. So I run a strace over "grep blah myfile | sort" and this is what I got: open("myfile", O_RDONLY|O_LARGEFILE) = 3 fstat64(3, {st_mode=S_IFREG|0600, st_size=84, ...}) = 0 read(3, "blah blah and blah cause of... (4 Replies)
Discussion started by: klam
4 Replies

4. UNIX for Advanced & Expert Users

strace

Hi Gurus, I need to trace a sqlplus session using strace. Can someone please provide me the syntax. sorry was not able to figure out by reading the man page. :-( i tried to do as below but getting the error xt33db006/u1/app/oracle/product/10.2.0/asm_1$ strace -f sqlplus '/as sysdba'... (0 Replies)
Discussion started by: p4cldba
0 Replies

5. Solaris

fssnap ioctl error

For some reason when I try to take a snapshot of the root slice on a particular machine I get an ioctl 22 error. I can't seem to find much on the problem by searching the internet other than some realtime processes such as ntp that use mlock can cause this to happen. I tried running it with truss... (2 Replies)
Discussion started by: ilikecows
2 Replies

6. UNIX for Advanced & Expert Users

strace

Hi, does anyone know the equivalent command of the following in AIX : $ strace -tp 15033 Process 15033 attached - interrupt to quit 11:28:06 gettimeofday({1257766086, 104118}, NULL) = 0 11:28:06 getrusage(RUSAGE_SELF, {ru_utime={2270, 615813}, ru_stime={0, 634903}, ...}) = 0 Thank you (6 Replies)
Discussion started by: big123456
6 Replies

7. UNIX for Advanced & Expert Users

Need help on strace output

Hi All, Good day, need some help on strace result. We're encountering oracle Database server connection slowness (using sqlplus login to db server, there have 1 or 2 secs delay) we had generated strace and provide to oracle to investigate, and they told us it look like OS problem (Our OS is Red... (4 Replies)
Discussion started by: klng
4 Replies

8. Android

Strace help

I need to run and monitor applications on Android Emulator. I am using the strace utility to monitor system calls. Everytime to start strace i need to manually start the application , get the process Id of the application and then give it to strace to start logging all the system calls. So is... (20 Replies)
Discussion started by: far001han
20 Replies

9. Ubuntu

Running strace command

I want to run the strace -p xxxx -o in a script to monitor a process that hangs sometimes and requires a restart, my question is if strace is constantly running in the background will it chew up system resources and cause the system slowness? (3 Replies)
Discussion started by: wereyou
3 Replies

10. Red Hat

Strace rpm requirement for RHEL 5.9

I have requirement for strace utility rpm package for RHEL 5.9. I have made a google for last 1 hr. but did not find the required one. Can any one help me out to find out the compatible rpm package of strace for Redhat 5.9 version (I require 64 bit version). (7 Replies)
Discussion started by: Anjan Ganguly
7 Replies

LEARN ABOUT LINUX

snp

SNP(4)                                                     BSD Kernel Interfaces Manual                                                     SNP(4)

NAME

     snp -- tty snoop interface

SYNOPSIS

     #include <sys/snoop.h>

     int
     ioctl(fd, SNPSTTY, &dev);

     int
     ioctl(fd, SNPGTTY, &dev);

     int
     ioctl(fd, FIONREAD, &result);

DESCRIPTION

     /dev/snp is a snoop device which allows users to attach to any tty and watch activities on it.  The kernel must be compiled with device snp,
     or the snp module must be loaded, for these devices to be available.

     To associate a given snp device with a tty to be observed, open the snp device and a tty device, and then issue the SNPSTTY ioctl on snp
     device.  The argument passed to the ioctl(2) is the address of a variable of type int, holding the file descriptor of a tty device.  To
     detach the snp device from a tty use a pointer to a value of -1.

     The SNPGTTY ioctl returns information about the current tty attached to the open snp device.

     The FIONREAD ioctl returns a positive value equal to the number of characters in a read buffer.  Special values defined are:

     SNP_OFLOW     device overflow occurred, device detached.

     SNP_TTYCLOSE  tty not attached.

     SNP_DETACH    snp device has been detached by user or tty device has been closed and detached.

SEE ALSO

     pty(4), sio(4), kldload(8), watch(8)

HISTORY

     The snp device first appeared in FreeBSD 2.1.  In FreeBSD 8.0 the snp driver was rewritten to work with the replaced TTY subsystem.

AUTHORS

     The author of the current implementation is Ed Schouten <ed@FreeBSD.org>.  Previous versions of snp were based on code written by
     Ugen J.S. Antsilevich <ugen@NetVision.net.il>.

BUGS

     This version of snp does not return proper error codes when calling FIONREAD.  It also does not allow SNPSTTY to detach itself from the TTY.

BSD                                                              November 5, 2008                                                              BSD
All times are GMT -4. The time now is 03:01 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy