«

Hi,
i want to save the keywords of an ini file in a struct, together with a
fpos_t. I think i´m right with the concept, but the access through fsetpos()
doesn´t work. The position is always wrong (except, in this example, the
first line).

My struct looks like this:
***
typedef struct {
char pname[32];
fpos_t pos;
} iniParam;

This routine reads the data and put it to "iniParam param[100]":
***
while (!feof (pFile)) {
fgetpos(pFile, &pos);
c=fgetc(pFile);
ungetc(c, pFile);
if(c == '#')
fgets (linebuf, 255, pFile);
else {
param[i].pos = pos;
fgets (linebuf, 255, pFile);
sscanf(linebuf, "%s", param[i].pname);
i++;
}
}

This routine reads the keywords and do a corresponding fscanf:
***
for(i=0; i<n; i++) {
if(strcmp(param[i].pname, "keyword1") == 0) {
pos = param[i].pos;
fsetpos(pFile, &pos);
fscanf(pFile, "%*s %d", &param1);
}
if(strcmp(param[i].pname, "keyword2") == 0) {
...

Don´t know why the access through a fpos_t position doesn´t work.
Thanks for any help, Chris

On Wed, 8 Oct 2003 03:26:26 +0200, "C. Sengstock" <>
wrote:

>Hi,
>i want to save the keywords of an ini file in a struct, together with a
>fpos_t. I think i´m right with the concept, but the access through fsetpos()
>doesn´t work. The position is always wrong (except, in this example, the
>first line).

It works for me with just two problems. The reading loop doesn't
detect end of file correctly as explained in the faq:

http://www.eskimo.com/~scs/C-faq/q12.2.html

Also blank lines and junk lines in the ini file result in invalid
entries in param[].

My advice is:
1. Check the return code of each library functions you call.
2. Post a complete but minimalist program, including the ini
file contents that demonstrate the problem.

>My struct looks like this:
>***
>typedef struct {
> char pname[32];
> fpos_t pos;
>} iniParam;
>
>This routine reads the data and put it to "iniParam param[100]":
>***
>while (!feof (pFile)) {
> fgetpos(pFile, &pos);
> c=fgetc(pFile);
> ungetc(c, pFile);
> if(c == '#')
> fgets (linebuf, 255, pFile);
> else {
> param[i].pos = pos;
> fgets (linebuf, 255, pFile);
> sscanf(linebuf, "%s", param[i].pname);
> i++;
> }
>}
>
>This routine reads the keywords and do a corresponding fscanf:
>***
>for(i=0; i<n; i++) {
> if(strcmp(param[i].pname, "keyword1") == 0) {
> pos = param[i].pos;
> fsetpos(pFile, &pos);
> fscanf(pFile, "%*s %d", &param1);
> }
> if(strcmp(param[i].pname, "keyword2") == 0) {
> ...
>
>Don´t know why the access through a fpos_t position doesn´t work.
>Thanks for any help, Chris

Nick.

about
http://www.eskimo.com/~scs/C-faq/q12.2.html
u can
while(fgets(buf, MAXLINE, infp) != NULL && !feof(infp))
{

}

"Nick Austin" <> wrote in message
news:...
> On Wed, 8 Oct 2003 03:26:26 +0200, "C. Sengstock" <>
> wrote:
>
> >Hi,
> >i want to save the keywords of an ini file in a struct, together with a
> >fpos_t. I think i´m right with the concept, but the access through
fsetpos()
> >doesn´t work. The position is always wrong (except, in this example, the
> >first line).
>
> It works for me with just two problems. The reading loop doesn't
> detect end of file correctly as explained in the faq:
>
> http://www.eskimo.com/~scs/C-faq/q12.2.html
>
> Also blank lines and junk lines in the ini file result in invalid
> entries in param[].
>
> My advice is:
> 1. Check the return code of each library functions you call.
> 2. Post a complete but minimalist program, including the ini
> file contents that demonstrate the problem.
>
> >My struct looks like this:
> >***
> >typedef struct {
> > char pname[32];
> > fpos_t pos;
> >} iniParam;
> >
> >This routine reads the data and put it to "iniParam param[100]":
> >***
> >while (!feof (pFile)) {
> > fgetpos(pFile, &pos);
> > c=fgetc(pFile);
> > ungetc(c, pFile);
> > if(c == '#')
> > fgets (linebuf, 255, pFile);
> > else {
> > param[i].pos = pos;
> > fgets (linebuf, 255, pFile);
> > sscanf(linebuf, "%s", param[i].pname);
> > i++;
> > }
> >}
> >
> >This routine reads the keywords and do a corresponding fscanf:
> >***
> >for(i=0; i<n; i++) {
> > if(strcmp(param[i].pname, "keyword1") == 0) {
> > pos = param[i].pos;
> > fsetpos(pFile, &pos);
> > fscanf(pFile, "%*s %d", &param1);
> > }
> > if(strcmp(param[i].pname, "keyword2") == 0) {
> > ...
> >
> >Don´t know why the access through a fpos_t position doesn´t work.
> >Thanks for any help, Chris
>
> Nick.
>

"Nick Austin" wrote:
> My advice is:
> 1. Check the return code of each library functions you call.
> 2. Post a complete but minimalist program, including the ini
> file contents that demonstrate the problem.

This is straighter to the point. The code should save the position of a
line, and do the output through that positions. But the code doesn´t work,
the output is:
-----------------------------
#dontreadthis <<< this is the "myfile.txt" data
baud = 4
#nodata

port = 50
parity = 6
<<< till here
*** output
#dontreadthis <<<< that´s the generated output through positions
this
= 4
ta
<<<< that´s the end
------------------------------------


the code looks like this:
-------------------------------------
fpos_t position[50];
FILE* fp;
char line[200];
int i, n;

fp = fopen("myfile.txt", "r");
if(!fp) perror("error opening file");
else {
i=0;
while(!feof(fp)) {
if(fgetpos(fp, &position[i]) != 0) {
printf("error getting position\n");
exit(1);
}
if(fgets(line, 200, fp)==NULL)
break;
printf("%s", line);
i++;
}
}
n=i;
printf("\n*** output\n");
for(i=0; i<n; i++) {
if(fsetpos(fp, &position[i]) != 0) {
printf("error setting position\n");
exit(1);
}
fgets(line, 200, fp);
printf("%s", line);
}
fclose(fp);
-----------------------------------------

Thanks, Chris

"C. Sengstock" wrote:
> "Nick Austin" wrote:
>
> > My advice is:
> > 1. Check the return code of each library functions you call.
> > 2. Post a complete but minimalist program, including the ini
> > file contents that demonstrate the problem.
>
> This is straighter to the point. The code should save the position
> of a line, and do the output through that positions. But the code
> doesn´t work, the output is:
>
.... snip ...

All complete C programs include an "int main(...) {" line, and
code cannot be generated outside of a function, which, in turn,
usually requires some sort of return statement.

Try again, with something that can be cut, pasted and compiled
unchanged. Do include the sample data again - you did that right.

--
Chuck F () ()
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net> USE worldnet address!

"CBFalconer" wrote:
> All complete C programs include an "int main(...) {" line, and
> code cannot be generated outside of a function, which, in turn,
> usually requires some sort of return statement.
Yep ... copy paste ready cody ...

#include<stdio.h>
#include<stdlib.h>
int main() {
fpos_t position[50];
FILE* fp;
char line[200];
int i, n;

fp = fopen("myfile.txt", "r");
if(!fp) perror("error opening file");
else {
i=0;
while(!feof(fp)) {
if(fgetpos(fp, &position[i]) != 0) {
printf("error getting position\n");
exit(1);
}
if(fgets(line, 200, fp)==NULL)
break;
printf("%s", line);
i++;
}
}
n=i;
printf("\n*** output\n");
for(i=0; i<n; i++) {
if(fsetpos(fp, &position[i]) != 0) {
printf("error setting position\n");
exit(1);
}
fgets(line, 200, fp);
printf("%s", line);
}
fclose(fp);
return 0;
}

Thanks, Chris

On Wed, 8 Oct 2003 14:19:49 +0200, "C. Sengstock" <>
wrote:

>This is straighter to the point. The code should save the position of a
>line, and do the output through that positions. But the code doesn´t work,
>the output is:
>-----------------------------
>#dontreadthis <<< this is the "myfile.txt" data
>baud = 4
>#nodata
>
>port = 50
>parity = 6
> <<< till here
>*** output
>#dontreadthis <<<< that´s the generated output through positions
>this
>= 4
>ta
> <<<< that´s the end
>------------------------------------

When I try the output is:

#dontreadthis
baud = 4
#nodata

port = 50
parity = 6

*** output
#dontreadthis
baud = 4
#nodata

port = 50
parity = 6

So the problem isn't in the code snippet you posted. You could
try asking again in a newsgroup for you compiler.

>the code looks like this:

#include <stdio.h>

int main( void )
{
> fpos_t position[50];
> FILE* fp;
> char line[200];
> int i, n;
>
> fp = fopen("myfile.txt", "r");
> if(!fp) perror("error opening file");
> else {
> i=0;
> while(!feof(fp)) {
> if(fgetpos(fp, &position[i]) != 0) {
> printf("error getting position\n");
> exit(1);
> }
> if(fgets(line, 200, fp)==NULL)
> break;
> printf("%s", line);
> i++;
> }
> }
> n=i;
> printf("\n*** output\n");
> for(i=0; i<n; i++) {
> if(fsetpos(fp, &position[i]) != 0) {
> printf("error setting position\n");
> exit(1);
> }
> fgets(line, 200, fp);
> printf("%s", line);
> }
> fclose(fp);
return 0;
}

Nick.

in comp.lang.c i read:

>while(fgets(buf, MAXLINE, infp) != NULL && !feof(infp))

the feof test is redundant.

--
a signature

C. Sengstock wrote:

>
> "CBFalconer" wrote:
>> All complete C programs include an "int main(...) {" line, and
>> code cannot be generated outside of a function, which, in turn,
>> usually requires some sort of return statement.
> Yep ... copy paste ready cody ...
>
> #include<stdio.h>
> #include<stdlib.h>
> int main() {
> fpos_t position[50];
> FILE* fp;
> char line[200];
> int i, n;
>
> fp = fopen("myfile.txt", "r");
> if(!fp) perror("error opening file");
You most probably want to exit as well at this point (or atleast avoid
reading from fp later on down below, by initializing i to 0).

> else {
> i=0;
> while(!feof(fp)) {
> if(fgetpos(fp, &position[i]) != 0) {
> printf("error getting position\n");
> exit(1);
exit(EXIT_FAILURE);

> }
> if(fgets(line, 200, fp)==NULL)
I would personally prefer to use sizeof(line) instead in this case.

> break;
> printf("%s", line);
> i++;
> }
> }
> n=i;
> printf("\n*** output\n");
> for(i=0; i<n; i++) {
> if(fsetpos(fp, &position[i]) != 0) {
> printf("error setting position\n");
> exit(1);
exit(EXIT_FAILURE);
> }
> fgets(line, 200, fp);
See above.

> printf("%s", line);
> }
> fclose(fp);
> return 0;
> }
>
> Thanks, Chris

What exactly is the problem you are encountering with this code? Are you
100% certain that none of your lines are more than 200 characters in
length?

-nrk.

"nrk" wrote:
> What exactly is the problem you are encountering with this code? Are you
> 100% certain that none of your lines are more than 200 characters in
> length?
Yep, size of line isn´t greater than 200. I really think the problem has to
do with the compiler (tcc or bcc32, both make this failure!). I tried a lot
of tests with fgetpos() and fsetpos(), but they all went wrong!

Chris