Thread: How to convert char read from file into string

#include <stdio.h>
#include <errno.h>
#include <string.h>


int main(int argc, char **argv)
{

FILE *f;
int c;
errno = 0;

/Check for no. of arguments and try opening file/
if (argc == 1)
{
printf("There is no file selected.\n");
printf("Usage: test <filename> <filename> \n");
}
else
{
for (int i = 1; i < argc; i++)
{
if((f = fopen(argv[i], "r")) == NULL)
{
printf("File: %s cannot be opened. \n", argv[i]);
fprintf(stderr, "Open file %s failed: %s\n", argv[i], strerror(errno));
}
else
{

/read from text file as characters/
while ((c = fgetc(f)) != EOF )
{
if(c == '"')
{
while((c = fgetc(f)) != '"')
{
putc(c, stdout);
}

Hi there....the above is what I have got so far. It checks for the number of arguments and open the files specified. The it reads from the text files that the file is specified.

Objectives:
To read the contents of the file, check validity for absolute reference to a file ie. hypertext starting with file:/
eg <a href="file:/example">. Should be recursive as well

Questions:
I have managed to check for < > and read any text inside the < > but I need to extract anything that is after file:/. I tried using fgets as well...but I cant seems to filter out text that is after the file:/.

Any help, suggestions and comments are welcome as I am still new with C.

Thanks

When you've read a <, copy all following chars to a buffer until you find the (matching) >.

Then call another routine to validate the contents of the buffer between the <> pair

Code:

void validate ( char *buff ) {
    printf( "buff=%s\n", buff );
}

This just prints the buffer you want to validate. I would suggest you leave it like this until your file reading loop is reliably extracting <> pairs from your input files.

Once it is, then you can focus on making validate() do what it's supposed to do

Hi Hammer.....

I am not very sure what you are trying to tell me
because it seems ok when I tested the codes out. It reads anything that is inside the " ". Could you please elaborate??

Thank you in advance...

while ((c = fgetc(f)) != '>')
{
sprintf(buffer, "%s");
validate(buffer);
if(c == EOF)
break;
}

Thanks....well..this is how I check for EOF, is there any other better way?? This way it will still print the stuff that is after < and before EOF.

And using sprintf, I attempt to read the characters into a char buffer[] but the result I get is quite gibberish.....why is that so?? Even when I use %s ??

> because it seems ok when I tested the codes out.
You're probably OK while your input files are well-formed HTML - that is, all the <> match up.
However, you're more likely to come unstuck with a bad HTML file, which contains a <, and no following > before the end of file

Here's my idea for building your buffer

Code:

#include <stdio.h>

void validate ( char *buff ) {
    printf( "%s\n", buff );
}

int main ( ) {
    char buff[BUFSIZ];
    int  i = 0;
    int  ch;
    while ( (ch=fgetc(stdin)) != EOF ) {
        if ( ch == '<' ) {
            /* found a <, now find the > */
            while ( (ch=fgetc(stdin)) != EOF && ch != '>' ) {
                /* also check i < BUFSIZ as well */
                buff[i++] = ch;
                buff[i] = '\0';
            }
            if ( i > 0 ) {
                validate( buff );
                i = 0;  /* ready for the next one */
            }
        }
    }
    return 0;
}

> Use fread() instead.
fread() has no benefits over fgetc for reading text files

I can have some rest now.........proggie is working.

Thanks everyone for your help.