fgetpos.md

description	title	ms.date	api_name	api_location	api_type	topic_type	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: fgetpos	fgetpos	4/2/2020	fgetpos _o_fgetpos	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-stdio-l1-1-0.dll	DLLExport	apiref	fgetpos	fgetpos function streams, file position indicator	bfa05c38-1135-418c-bda1-d41be51acb62

fgetpos

Gets a stream's file-position indicator.

Syntax

int fgetpos(
   FILE *stream,
   fpos_t *pos
);

Parameters

stream
Target stream.

pos
Position-indicator storage.

Return value

If successful, fgetpos returns 0. On failure, it returns a nonzero value and sets errno to one of the following manifest constants (defined in STDIO.H): EBADF, which means the specified stream isn't a valid file pointer or isn't accessible, or EINVAL, which means the stream value or the value of pos is invalid, such as if either is a null pointer. If stream or pos is a NULL pointer, the function invokes the invalid parameter handler, as described in Parameter validation.

Remarks

The fgetpos function gets the current value of the stream argument's file-position indicator and stores it in the object pointed to by pos. The fsetpos function can later use information stored in pos to reset the stream argument's pointer to its position at the time fgetpos was called. The pos value is stored in an internal format and is intended for use only by fgetpos and fsetpos.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

Function	Required header
fgetpos	<stdio.h>

For more compatibility information, see Compatibility.

Example

// crt_fgetpos.c
// This program uses fgetpos and fsetpos to
// return to a location in a file.

#include <stdio.h>

int main( void )
{
   FILE   *stream;
   fpos_t pos;
   char   buffer[20];

   if( fopen_s( &stream, "crt_fgetpos.txt", "rb" ) ) {
      perror( "Trouble opening file" );
      return -1;
   }

   // Read some data and then save the position.
   fread( buffer, sizeof( char ), 8, stream );
   if( fgetpos( stream, &pos ) != 0 ) {
      perror( "fgetpos error" );
      return -1;
   }

   fread( buffer, sizeof( char ), 13, stream );
   printf( "after fgetpos: %.13s\n", buffer );

   // Restore to old position and read data
   if( fsetpos( stream, &pos ) != 0 ) {
      perror( "fsetpos error" );
      return -1;
   }

   fread( buffer, sizeof( char ), 13, stream );
   printf( "after fsetpos: %.13s\n", buffer );
   fclose( stream );
}

Input: crt_fgetpos.txt

fgetpos gets a stream's file-position indicator.

Output crt_fgetpos.txt

after fgetpos: gets a stream
after fsetpos: gets a stream

See also

Stream I/O
fsetpos