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Full Discussion: Malloc problem with fread() to read file to structure in C
Top Forums Programming Malloc problem with fread() to read file to structure in C Post 302887784 by Don Cragun on Monday 10th of February 2014 07:27:17 PM
Old 02-10-2014
When I run the code you showed us in message #8 in this thread, the output I get is:
Code:
24 bytes allocated at 0x10a000890 for linked list element
7 bytes allocated at 0x10a0008b0 for name Angola

24 bytes allocated at 0x10a0008c0 for linked list element
10 bytes allocated at 0x10a0008e0 for name Bangalore

24 bytes allocated at 0x10a0008f0 for linked list element
6 bytes allocated at 0x10a000910 for name Cairo

24 bytes allocated at 0x10a000920 for linked list element
7 bytes allocated at 0x10a000940 for name Dallas

24 bytes allocated at 0x10a000950 for linked list element
9 bytes allocated at 0x10a000970 for name Edmonton

24 bytes allocated at 0x10a000980 for linked list element
6 bytes allocated at 0x10a0009a0 for name Fargo

24 bytes allocated at 0x10a0009b0 for linked list element
8 bytes allocated at 0x10a0009d0 for name Georgia

24 bytes allocated at 0x10a0009e0 for linked list element
8 bytes allocated at 0x10a000a00 for name Halifax

24 bytes allocated at 0x10a000a10 for linked list element
13 bytes allocated at 0x10a000a30 for name Indianapolis

24 bytes allocated at 0x10a000a40 for linked list element
8 bytes allocated at 0x10a000a60 for name Jamaica

End-of-file found on input.

Printing list element located at 0x10a000890:
roll_num: 10001	name: Angola
roll_num: 10002	name: Bangalore
roll_num: 10003	name: Cairo
roll_num: 10004	name: Dallas
roll_num: 10005	name: Edmonton
roll_num: 10006	name: Fargo
roll_num: 10007	name: Georgia
roll_num: 10008	name: Halifax
roll_num: 10009	name: Indianapolis
roll_num: 10010	name: Jamaica

As you can see, this is considerably different from the output you said you got from this code in message #6 in this thread. But, most importantly the roll_num values shown while walking the linked list match the values found in your input file. I'm not doing anything with atoi(), calloc(), exit(), fclose(), ferror(), fgets(), fopen(), fprintf(), free(), malloc(), printf(), strlen(), or strncpy() that should behave differently on OS X than it should on any Linux distribution. I can't see how you would get the values for roll_num that you showed us in message #6 in this thread from the code you posted in message #8 in this thread.
Last edited by Don Cragun; 02-10-2014 at 08:28 PM.. Reason: Remove duplicated text from cut & paste error.
This User Gave Thanks to Don Cragun For This Post:
yifangt
 

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