function
<cstdio>
fgetpos
int fgetpos ( FILE * stream, fpos_t * pos );
Get current position in stream
Retrieves the current position in the stream.
The function fills the fpos_t object pointed by pos with the information needed from the stream's position indicator to restore the stream to its current position (and multibyte state, if wide-oriented) with a call to fsetpos.
The ftell function can be used to retrieve the current position in the stream as an integer value.
Parameters
- stream
- Pointer to a FILE object that identifies the stream.
- pos
- Pointer to a fpos_t object.
This should point to an object already allocated.
Return Value
On success, the function returns zero.
In case of error, errno is set to a platform-specific positive value and the function returns a non-zero value.
Example
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/* fgetpos example */
#include <stdio.h>
int main ()
{
FILE * pFile;
int c;
int n;
fpos_t pos;
pFile = fopen ("myfile.txt","r");
if (pFile==NULL) perror ("Error opening file");
else
{
c = fgetc (pFile);
printf ("1st character is %c\n",c);
fgetpos (pFile,&pos);
for (n=0;n<3;n++)
{
fsetpos (pFile,&pos);
c = fgetc (pFile);
printf ("2nd character is %c\n",c);
}
fclose (pFile);
}
return 0;
}
|
1st character is A
2nd character is B
2nd character is B
2nd character is B
|
The example opens myfile.txt, then reads the first character once, and then reads 3 times the same second character.
See also
- fsetpos
- Set position indicator of stream (function)
- ftell
- Get current position in stream (function)
- fseek
- Reposition stream position indicator (function)