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Top Forums Programming Scanf() string pointer problem Post 302874171 by Corona688 on Thursday 14th of November 2013 11:05:39 AM
Old 11-14-2013
char *studentName; is a pointer to a string. What does it point to? Absolutely nothing and nowhere in particular. It might point to invalid memory and crash immediately. It might point to somewhere in your own stack frame, causing it to crash later in fascinating nondeterministic ways.

The correct solution would be to either
1) Use line 8
2) Point it to valid memory with a line like list[x].studentName=malloc(20);

Last edited by Corona688; 11-14-2013 at 12:16 PM..
This User Gave Thanks to Corona688 For This Post:
 

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expand_dump(8)						      System Manager's Manual						    expand_dump(8)

NAME
expand_dump - Produces a non-compressed kernel crash dump file SYNOPSIS
/usr/sbin/expand_dump input-file output-file DESCRIPTION
By default, kernel crash dump files (vmzcore.#) are compressed during the crash dump. Compressed core files can be examined by the latest versions of debugging tools that have been recompiled to support compressed crash dump files. However, not all debugging tools may be upgraded on a given system, or you may want to examine a crash dump from a remote system using an older version of a tool. The expand_dump utility produces a file that can be read by tools that have not been upgraded to support compressed crash dump files. This non-compressed version can also be read by any upgraded tool. This utility can only be used with compressed crash dump files, and does not support any other form of compressed file. You cannot use other decompression tools such as compress, gzip, or zip on a compressed crash dump file. Note that the non-compressed file will require significantly more disk storage space as it is possible to achieve compression ratios of up to 60:1. Check the available disk space before running expand_dump and estimate the size of the non-compressed file as follows: Run tests by halting your system and forcing a crash as described in the Kernel Debugging manual. Use an upgraded debugger to determine the value of the variable dumpsize. Multiply this vale by the 8Kb page size to approximate the required disk space of the non-compressed crash-dump. Run expand_dump and pipe the output file to /dev/null, noting the size of the file that is printed when expand_dump completes its task. RETURN VALUES
Successful completion of the decompression. The user did not supply the correct number of command line arguments. The input file could not be read. The input file is not a compressed dump, or is corrupted. The output file could not be created or opened for writing and truncated. There was some problem writing to the output file (probably a full disk). The input file is not formated consistantly. It is probably corrupted. The input file could not be correctly decompressed. It is probably corrupted. EXAMPLES
expand_dump vmzcore.4 vmcore.4 SEE ALSO
Commands: dbx(1), kdbx(8), ladebug(1), savecore(8) Kernel Debugging System Administration expand_dump(8)
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