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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 302887771 by Don Cragun on Monday 10th of February 2014 05:50:58 PM
Old 02-10-2014
What OS are you using?
What is the size of the following types in your programming environment:
  1. int
  2. char *
  3. struct student *
  4. struct student
What were the sizes of the buffers allocated by the calls to malloc() and calloc() that you deleted from the output my code produced?

The output you showed in message #6 in this thread is missing newline and tab characters that my code writes and has changed a tab character to a constant string of four spaces? Did you modify my code? Did you modify the output it produced (other than removing the first two sections of the output)? If these alterations were done by the way you copy and paste code for display here, please redirect the output to a file (such as output.txt) and upload that text.

Please also upload the source you compiled so I can compare it with what I compiled.
 

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LEARN ABOUT MINIX

yacc

YACC(1) 						      General Commands Manual							   YACC(1)

NAME

       yacc - an LALR(1) parser generator

SYNOPSIS

       yacc [ -dlrtv ] [ -b file_prefix ] [ -p symbol_prefix ] filename

DESCRIPTION

       Yacc  reads  the  grammar specification in the file filename and generates an LR(1) parser for it.  The parsers consist of a set of LALR(1)
       parsing tables and a driver routine written in the C programming language.  Yacc normally writes the parse tables and the driver routine to
       the file y.tab.c.

       The following options are available:

	      -b file_prefix
		     The -b option changes the prefix prepended to the output file names to the string denoted by file_prefix.	The default prefix
		     is the character y.

	      -d     The -d option causes the header file y.tab.h to be written.

	      -l     If the -l option is not specified, yacc will insert #line directives in the generated code.  The #line directives let  the  C
		     compiler  relate  errors  in  the	generated  code to the user's original code.  If the -l option is specified, yacc will not
		     insert the #line directives.  #line directives specified by the user will be retained.

	      -p symbol_prefix
		     The -p option changes the prefix prepended to yacc-generated symbols to the string denoted  by  symbol_prefix.   The  default
		     prefix is the string yy.

	      -r     The  -r  option  causes  yacc to produce separate files for code and tables.  The code file is named y.code.c, and the tables
		     file is named y.tab.c.

	      -t     The -t option changes the preprocessor directives generated by yacc so that debugging statements will be incorporated in  the
		     compiled code.

	      -v     The -v option causes a human-readable description of the generated parser to be written to the file y.output.

       If the environment variable TMPDIR is set, the string denoted by TMPDIR will be used as the name of the directory where the temporary files
       are created.

FILES

       y.code.c
       y.tab.c
       y.tab.h
       y.output
       /tmp/yacc.aXXXXXX
       /tmp/yacc.tXXXXXX
       /tmp/yacc.uXXXXXX

DIAGNOSTICS

       If there are rules that are never reduced, the number of such rules is reported on standard error.  If there are any LALR(1) conflicts, the
       number of conflicts is reported on standard error.

4.3 Berkeley Distribution					   July 15, 1990							   YACC(1)
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