Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

Void-valued Function to extract substring from a string

Posted on 1997-04-05
1
Medium Priority
?
259 Views
Last Modified: 2010-04-10
I need help in writing a a void-valued function to extract a substring from an existing string.

For Example:
     char   sub[80];
     ...
     substr ('Converting to C', 7, 4, &sub);

would store the string 'ting' into the variable called 'sub'. The function should store a NUL character at the end of the extracted string.
0
Comment
Question by:cyrax
1 Comment
 

Accepted Solution

by:
linpage earned 100 total points
ID: 1162578
the following will do it.  However most 'c' programmers would probably make your example substr('Converting to C', 6, 4, &sub);   because of the 0 offset convention (change the line to while ( *src && start-- > 0) for this).  This snippet tests for the
src running out, but not the destination buffer.  You might want
to include a length for dest to be on the safe side.

void substr(const char* src, int start, int len, char ** dest)
{
  while ( *src && --start > 0)
      src++;
 
  while ( *src && len > 0)
  {
    **dest = *src;
    *dest++;
    src++;
    len--;
  }
  **dest = 0x00;
}
0

Featured Post

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Written by John Humphreys C++ Threading and the POSIX Library This article will cover the basic information that you need to know in order to make use of the POSIX threading library available for C and C++ on UNIX and most Linux systems.   [s…
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
The goal of the tutorial is to teach the user how to use functions in C++. The video will cover how to define functions, how to call functions and how to create functions prototypes. Microsoft Visual C++ 2010 Express will be used as a text editor an…
The viewer will learn how to clear a vector as well as how to detect empty vectors in C++.

782 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question