./match_pattern.out: malloc(): memory corruption: 0x0000000013a11600 *** Post: 302553849

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Top Forums Programming ./match_pattern.out: malloc(): memory corruption: 0x0000000013a11600 *** Post 302553849 by JohnGraham on Friday 9th of September 2011 02:56:10 AM

09-09-2011

Registered User

Quote:

Originally Posted by shoaibjameel123

I reckon its the problem with malloc(), free() pair.

Memory corruption is normally due to you straying outside the bounds of an array - not with malloc()/free() statements matching up. You've probably overwritten some of the space next to a malloc()'d portion of memory that glibc expects to be able to use for keeping track of the memory region - go through with a debugger and have a look for bounds errors.

As an aside, here's the sort of thing you can expect if you did have a problem with malloc()/free() pairs:

Code:

[john@john-laptop tmp.u6Q7IbZntd]$ cat prog.c
#include <stdlib.h>

int main(void)
{
    void *p = malloc(1);
    free(p);
    free(p);
    return 0;
}
[john@john-laptop tmp.u6Q7IbZntd]$ gcc prog.c -o prog
[john@john-laptop tmp.u6Q7IbZntd]$ ./prog
*** glibc detected *** ./prog: double free or corruption (fasttop): 0x09ba3008 ***
======= Backtrace: =========
/lib/libc.so.6(+0x6c501)[0x58b501]
/lib/libc.so.6(+0x6dd70)[0x58cd70]
/lib/libc.so.6(cfree+0x6d)[0x58fe5d]
./prog[0x8048425]
/lib/libc.so.6(__libc_start_main+0xe7)[0x535ce7]
./prog[0x8048361]
======= Memory map: ========
0051f000-00676000 r-xp 00000000 08:04 2793795    /lib/libc-2.12.1.so
00676000-00678000 r--p 00157000 08:04 2793795    /lib/libc-2.12.1.so
00678000-00679000 rw-p 00159000 08:04 2793795    /lib/libc-2.12.1.so
00679000-0067c000 rw-p 00000000 00:00 0 
0091c000-0091d000 r-xp 00000000 00:00 0          [vdso]
00ab9000-00ad3000 r-xp 00000000 08:04 2793551    /lib/libgcc_s.so.1
00ad3000-00ad4000 r--p 00019000 08:04 2793551    /lib/libgcc_s.so.1
00ad4000-00ad5000 rw-p 0001a000 08:04 2793551    /lib/libgcc_s.so.1
00dd4000-00df0000 r-xp 00000000 08:04 2793792    /lib/ld-2.12.1.so
00df0000-00df1000 r--p 0001b000 08:04 2793792    /lib/ld-2.12.1.so
00df1000-00df2000 rw-p 0001c000 08:04 2793792    /lib/ld-2.12.1.so
08048000-08049000 r-xp 00000000 08:04 1220779    /tmp/tmp.u6Q7IbZntd/prog
08049000-0804a000 r--p 00000000 08:04 1220779    /tmp/tmp.u6Q7IbZntd/prog
0804a000-0804b000 rw-p 00001000 08:04 1220779    /tmp/tmp.u6Q7IbZntd/prog
09ba3000-09bc4000 rw-p 00000000 00:00 0          [heap]
b7500000-b7521000 rw-p 00000000 00:00 0 
b7521000-b7600000 ---p 00000000 00:00 0 
b76fc000-b76fd000 rw-p 00000000 00:00 0 
b7714000-b7716000 rw-p 00000000 00:00 0 
bffdf000-c0000000 rw-p 00000000 00:00 0          [stack]
Aborted

JohnGraham

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mac2unix

dos2unix(1)						      General Commands Manual						       dos2unix(1)

NAME

       dos2unix - DOS/MAC to UNIX text file format converter

SYNOPSYS

       dos2unix [options] [-c convmode] [-o file ...] [-n infile outfile ...]

       Options:

       [-hkqV] [--help] [--keepdate] [--quiet] [--version]

DESCRIPTION

       This manual page documents dos2unix, the program that converts plain text files in DOS/MAC format to UNIX format.

OPTIONS

       The following options are available:

       -h --help
	      Print online help.

       -k --keepdate
	      Keep the date stamp of output file same as input file.

       -q --quiet
	      Quiet mode. Suppress all warning and messages.

       -V --version
	      Prints version information.

       -c --convmode convmode
	      Sets conversion mode. Simulates dos2unix under SunOS.

       -o --oldfile file ...
	      Old file mode. Convert the file and write output to it. The program default to run in this mode. Wildcard names may be used.

       -n --newfile infile outfile ...
	      New  file  mode.	Convert the infile and write output to outfile. File names must be given in pairs and wildcard names should NOT be
	      used or you WILL lost your files.

EXAMPLES

       Get input from stdin and write output to stdout.

	      dos2unix

       Convert and replace a.txt. Convert and replace b.txt.

	      dos2unix a.txt b.txt

	      dos2unix -o a.txt b.txt

       Convert and replace a.txt in ASCII conversion mode.  Convert and replace b.txt in ISO conversion mode.  Convert	c.txt  from  Mac  to  Unix
       ascii format.

	      dos2unix a.txt -c iso b.txt

	      dos2unix -c ascii a.txt -c iso b.txt

	      dos2unix -c mac a.txt b.txt

       Convert and replace a.txt while keeping original date stamp.

	      dos2unix -k a.txt

	      dos2unix -k -o a.txt

       Convert a.txt and write to e.txt.

	      dos2unix -n a.txt e.txt

       Convert a.txt and write to e.txt, keep date stamp of e.txt same as a.txt.

	      dos2unix -k -n a.txt e.txt

       Convert and replace a.txt. Convert b.txt and write to e.txt.

	      dos2unix a.txt -n b.txt e.txt

	      dos2unix -o a.txt -n b.txt e.txt

       Convert c.txt and write to e.txt. Convert and replace a.txt.  Convert and replace b.txt. Convert d.txt and write to f.txt.

	      dos2unix -n c.txt e.txt -o a.txt b.txt -n d.txt f.txt

DIAGNOSTICS

BUGS

       The program does not work properly under MSDOS in stdio processing mode.  If you know why is that so, please tell me.

AUTHORS

       Benjamin Lin - <blin@socs.uts.edu.au>

       Bernd Johannes Wuebben (mac2unix mode) <wuebben@kde.org>

MISCELLANY

       Tested environment:

	      Linux 1.2.0 with GNU C 2.5.8

	      SunOS 4.1.3 with GNU C 2.6.3

	      MS-DOS 6.20 with Borland C++ 4.02

       Suggestions and bug reports are welcome.

SEE ALSO

       unix2dos(1) mac2unix(1)

1995.03.31							   dos2unix v3.0						       dos2unix(1)