Everytime i compile this program the pointer seems to lose its data??
*fileToFix is suppose to change after entering fixFile() as a param
program ------------------------------------------------
#include <iostream.h>
void fileFix(char*[], char type);
int main() {
char* fileToFix[30];
*fileToFix = "file";
fileFix(fileToF ix, 'g');
cout << flush << endl;
cout << "Finished File: " << *fileToFix << endl;
return 0;
}
void fileFix(char *fileToFix[], char type) {
cout << "*fileToFix = " << *fileToFix << endl;
int pos = 0;
bool goOn = true;
char suff[] = {'.','d','a','t '};
char fileFix[30];
char fCopy[30];
fCopy[0] = type;
strcpy(fileFix, *fileToFix);
for (int i = 1; i < 30; i++)
fCopy[i] = fileFix[i-1];
for (int i = 0; i < 30; i++) {
if (((int)fCopy[i] < 65) || ((int)fCopy[i] > 90 && (int)fCopy[i] < 97) ||
((int)fCopy[i] > 122)) {
goOn = false;
pos = i;
}
if (!goOn)
break;
}
for (int j = 0; j < 4; j++)
fCopy[pos+j] = suff[j];
for (int i = pos+4; i < 30; i++)
fCopy[i] = '\0';
*fileToFix = fCopy;
cout << "end: *fileToFix = " << *fileToFix << endl;
}
end of program -----
please helpppppppppppp p
carl 1 1225
Sh0t wrote: Everytime i compile this program the pointer seems to lose its data?? *fileToFix is suppose to change after entering fixFile() as a param
program ------------------------------------------------
#include <iostream.h> void fileFix(char*[], char type);
Perhaps you meant (see below):
void fileFix(char *, char type);
or
void fileFix(char [], char type);
In these two examples, the first parameter is
a pointer to char, not an array of pointers.
In general, when passing arrays to function, one
passes the array (or a pointer to the first location
in the array) and the length. Since your function
does not have an array length parameter, I conclude
that you don't want an array of pointers.
int main() { char* fileToFix[30];
Do you realize that you are declaring an array of
30 pointers?
Did you mean:
char fileToFix[30]; /* a C string of 30 chars */
Or perhaps you want:
std::string fileToFix;
*fileToFix = "file";
This is not what you wanted. This line takes a pointer
to the literal "file" and places it into first location
of the array fileToFix.
Some alternatives:
char fileToFix[30];
strcpy(fileToFi x, "file");
or
std::string fileToFix;
fileToFix = "file"; fileFix(fileToF ix, 'g');
This line depends on the true meaning of the first
parameter. cout << flush << endl; cout << "Finished File: " << *fileToFix << endl; return 0; }
[snip] end of program -----
please helpppppppppppp p
carl
You need to differentiate between the following
concepts:
1. chars
2. an array of chars.
3. a null or zero terminated array of chars,
often called a C-style string.
4. The std::string type.
5. Constant string literals.
See the FAQs below for more information.
--
Thomas Matthews
C++ newsgroup welcome message: http://www.slack.net/~shiva/welcome.txt
C++ Faq: http://www.parashift.com/c++-faq-lite
C Faq: http://www.eskimo.com/~scs/c-faq/top.html
alt.comp.lang.l earn.c-c++ faq: http://www.comeaucomputing.com/learn/faq/
Other sites: http://www.josuttis.com -- C++ STL Library book http://www.sgi.com/tech/stl -- Standard Template Library This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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