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Diffstat (limited to 'newlib/libc/stdio/ftell.c')
| -rw-r--r-- | newlib/libc/stdio/ftell.c | 142 |
1 files changed, 0 insertions, 142 deletions
diff --git a/newlib/libc/stdio/ftell.c b/newlib/libc/stdio/ftell.c deleted file mode 100644 index 5cd3987c0..000000000 --- a/newlib/libc/stdio/ftell.c +++ /dev/null @@ -1,142 +0,0 @@ -/* - * Copyright (c) 1990 The Regents of the University of California. - * All rights reserved. - * - * Redistribution and use in source and binary forms are permitted - * provided that the above copyright notice and this paragraph are - * duplicated in all such forms and that any documentation, - * advertising materials, and other materials related to such - * distribution and use acknowledge that the software was developed - * by the University of California, Berkeley. The name of the - * University may not be used to endorse or promote products derived - * from this software without specific prior written permission. - * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR - * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED - * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. - */ - -/* -FUNCTION -<<ftell>>, <<ftello>>---return position in a stream or file - -INDEX - ftell -INDEX - ftello - -ANSI_SYNOPSIS - #include <stdio.h> - long ftell(FILE *<[fp]>); - off_t ftello(FILE *<[fp]>); - -TRAD_SYNOPSIS - #include <stdio.h> - long ftell(<[fp]>) - FILE *<[fp]>; - - off_t ftello(<[fp]>) - FILE *<[fp]>; - -DESCRIPTION -Objects of type <<FILE>> can have a ``position'' that records how much -of the file your program has already read. Many of the <<stdio>> functions -depend on this position, and many change it as a side effect. - -The result of <<ftell>>/<<ftello>> is the current position for a file -identified by <[fp]>. If you record this result, you can later -use it with <<fseek>>/<<fseeko>> to return the file to this -position. The difference between <<ftell>> and <<ftello>> is that -<<ftell>> returns <<long>> and <<ftello>> returns <<off_t>>. - -In the current implementation, <<ftell>>/<<ftello>> simply uses a character -count to represent the file position; this is the same number that -would be recorded by <<fgetpos>>. - -RETURNS -<<ftell>>/<<ftello>> return the file position, if possible. If they cannot do -this, they return <<-1L>>. Failure occurs on streams that do not support -positioning; the global <<errno>> indicates this condition with the -value <<ESPIPE>>. - -PORTABILITY -<<ftell>> is required by the ANSI C standard, but the meaning of its -result (when successful) is not specified beyond requiring that it be -acceptable as an argument to <<fseek>>. In particular, other -conforming C implementations may return a different result from -<<ftell>> than what <<fgetpos>> records. - -<<ftello>> is defined by the Single Unix specification. - -No supporting OS subroutines are required. -*/ - -#if defined(LIBC_SCCS) && !defined(lint) -static char sccsid[] = "%W% (Berkeley) %G%"; -#endif /* LIBC_SCCS and not lint */ - -/* - * ftell: return current offset. - */ - -#include <stdio.h> -#include <errno.h> - -#include "local.h" - -long -_DEFUN (ftell, (fp), - register FILE * fp) -{ - fpos_t pos; - - _flockfile(fp); - - /* Ensure stdio is set up. */ - - CHECK_INIT (fp); - - if (fp->_seek == NULL) - { - fp->_data->_errno = ESPIPE; - _funlockfile(fp); - return -1L; - } - - /* Find offset of underlying I/O object, then - adjust for buffered bytes. */ - fflush(fp); /* may adjust seek offset on append stream */ - if (fp->_flags & __SOFF) - pos = fp->_offset; - else - { - pos = (*fp->_seek) (fp->_cookie, (fpos_t) 0, SEEK_CUR); - if (pos == -1L) - { - _funlockfile(fp); - return pos; - } - } - if (fp->_flags & __SRD) - { - /* - * Reading. Any unread characters (including - * those from ungetc) cause the position to be - * smaller than that in the underlying object. - */ - pos -= fp->_r; - if (HASUB (fp)) - pos -= fp->_ur; - } - else if (fp->_flags & __SWR && fp->_p != NULL) - { - /* - * Writing. Any buffered characters cause the - * position to be greater than that in the - * underlying object. - */ - pos += fp->_p - fp->_bf._base; - } - - _funlockfile(fp); - return pos; -} |