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Full Discussion: help with data type sizes
Top Forums Programming help with data type sizes Post 302489706 by fpmurphy on Friday 21st of January 2011 10:48:07 AM
Old 01-21-2011
I am going to close this thread. It is veering off-topic.

However I would like to point out that C and C++ have a special type defined for pointer arithmetic, namely ptrdiff_t, which is a typedef of a platform-specific signed integral type.

You can use a variable of type ptrdiff_t to store the result of subtracting or adding pointers as shown in the following simple example:
Code:
#include <stdlib.h>
int main()
{
  int buf[10];
  ptrdiff_t diff = (&buf[4]) - buf;                   // diff = 4
  diff = buf -(&buf[6]);                              // diff =  -6
}

What are the advantages of ptrdiff_t? Self-documenting and portability - the underlying type may vary across programming models but porting requires no source code changes.
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CUT-DIFF(1)							  Cutter's manual						       CUT-DIFF(1)

NAME
cut-diff - show difference between 2 files with color SYNOPSIS
cut-diff [option ...] file1 file2 DESCRIPTION
cut-diff is a diff command that uses diff feature in Cutter. It shows difference with color. It's recommended that you use a normal diff(1) when you want to use with patch(1) or you don't need color. OPTIONS
--version cut-diff shows its own version and exits. -c [yes|true|no|false|auto], --color=[yes|true|no|false|auto] If 'yes' or 'true' is specified, cut-diff uses colorized output by escape sequence. If 'no' or 'false' is specified, cut-diff never use colorized output. If 'auto' or the option is omitted, cut-diff uses colorized output if available. The default is auto. -u, --unified cut-diff uses unified diff format. --context-lines=LINES Shows diff context around LINES. All lines are shown by default. When unified diff format is used, 3 lines are shown by default. --label=LABEL, -L=LABEL Uses LABEL as a header label. The first--label option value is used as file1's label and the second --label option value is used asfile2's label. Labels are the same as file names by default. EXIT STATUS
The exit status is 0 for success, non-0 otherwise. TODO: 0 for non-difference, 1 for difference and non-0 for errors. EXAMPLE
In the following example, cut-diff shows difference between file1 and file2: % cut-diff file1 file2 In the following example, cut-diff shows difference between file1 and file2 with unified diff format: % cut-diff -u file1 file2 SEE ALSO
diff(1) Cutter February 2011 CUT-DIFF(1)
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