hello,everyone,I'm reading LDD3.Topics about oops,it said the code bellow would cause a fault condition because "this method copies a string to a local variable,unfortunately,the string is longer than the destination array".Well,hard to understand....Is that right?I thought the fault should be caused by the wrong memset,it overwrite the function stack,the value of __user is 0xff now.will anyone tell me what happened here?Thanks;
It's writing 20 bytes to an array 4 bytes long, rampaging 16 more bytes across memory it shouldn't, trashing things like local variable values, function parameters, and return locations, all of which are kept in the same general area of stack here.
You're both right, in other words. There's many possible problems that could be caused by this, not just corruption of the return vector. If you're lucky, it crashes immediately. If you're unlucky, it puts bizarre values into your local variables and function parameters, causing behavior that's very difficult to rationally explain.
Solaris 2.6, using CDE:
agh. I accidentally set an ugly palette as my Home Session. The problem is, when I change the palette back to Default, I am informed that my change will be apparent in my next session. But when I log out and in, it's still the Ugly Palette. Doesn't matter if I set the... (1 Reply)
When ever i mount any of my 2 scsi cdroms, I get a kernel crash with the folfollowing oops kernel output.
I understand that it is impossible to anwser my question WHY but could you give me some advice where i should look to debug the problem or advice me some tools to detect what might be... (3 Replies)
I have directory/dns server running sparc solaris 9.
while troubleshooting another issue, i overwrote the aliases file on accident.
my question is: is there any way to revert this?
any help super appreciated...especially since this a production box! (2 Replies)
Hi All,
Can any one please differenciate between the Data Abstraction and Encapsulation? If possible, with code.
Thanks in Advance,
Naga:cool: (2 Replies)
I've been tearing my hair out over this: vsftp does not work on any of my RedHat Server 5.x systems - I keep getting a variation on 500 OOPS: vsftpd: cannot locate user specified in 'ftp_username':ftp or 500 OOPS: cannot locate user entry:nobody (different errors on different systems). I spent... (2 Replies)
Hi all,
When i load my block device driver in Fedoracore10 kernel 2.6.27. i got this type of error kernel panic - not syncing : Fatal exception in interrupt. I am unable to save the log file....
Can any one help me.....
regards
sundar (4 Replies)
I can belive I really did this... chmod 777 /home :eek:
I have my /home directory synced to another machine.
Can anyone tell me how to get the permissions from
back up server /home to production server /home
It's important that I dont over write the files on the... (1 Reply)
I've been fighting this for about a year: vsftp does not work on any of my RedHat Server 5.x systems - I keep getting a variation on 500 OOPS: vsftpd: cannot locate user specified in 'ftp_username':ftp or 500 OOPS: cannot locate user entry:nobody (different errors on different systems). I spent... (0 Replies)
Discussion started by: thomn8r
0 Replies
LEARN ABOUT OSF1
mkstr
mkstr(1) General Commands Manual mkstr(1)NAME
mkstr - Creates an error message file
SYNOPSIS
mkstr [-] message_file prefix file...
The mkstr command is used to create files of error messages that can be removed from a single C source file, or from multiple source files.
OPTIONS
Causes messages to be appended to the specified message file, instead of creating a new file.
DESCRIPTION
The use of mkstr can reduce the size of programs that contain many error diagnostics and reduce system overhead in running such programs.
The mkstr command processes each of the specified files, placing an altered version of the input file in a file whose name consists of the
specified prefix and the original name.
To process the error messages in the source to the message file, mkstr keys on the string 'error(' in the input stream. Each time it
occurs, the C string starting at the '' is placed in the message file and is followed by a null character and a newline character. The
null character terminates the message so it can be easily used when retrieved; the newline character makes it possible to catalog the error
message file neatly to see its contents.
The altered copy of the input file then contains a lseek() pointer into the file that can be used to retrieve the message to its appropri-
ate source file, as shown in the following example of a program that mkstr produces.
char efilname[] = "/usr/lib/pi_strings"; int efil = -1;
error(int a1, int a2, int a3, int a4) {
char buf[256];
if (efil < 0) {
efil = open(efilname, 0);
if (efil < 0) { oops:
perror(efilname);
exit(1);
}
}
if ((lseek(efil, (long) a1, 0)) == (long)-1 ) ||
read(efil, buf, 256) <= 0)
goto oops;
printf(buf, a2, a3, a4); }
EXAMPLES
To put the error messages from the current directory C source files into a file called pi_strings, and to put processed copies of the
source for these files into filenames prefixed by xx, enter: mkstr pi_strings xx *.c To append the error messages from an additional source
file to pi_strings, enter: mkstr - pi_strings xx newfile.c
SEE ALSO
Commands: xstr(1)
Functions: lseek(2)mkstr(1)