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Diffstat (limited to 'newlib/libc/stdio/fgetpos.c')
-rw-r--r-- | newlib/libc/stdio/fgetpos.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/newlib/libc/stdio/fgetpos.c b/newlib/libc/stdio/fgetpos.c new file mode 100644 index 0000000..214021a --- /dev/null +++ b/newlib/libc/stdio/fgetpos.c @@ -0,0 +1,61 @@ +/* +FUNCTION +<<fgetpos>>---record position in a stream or file + +INDEX + fgetpos + +ANSI_SYNOPSIS + #include <stdio.h> + int fgetpos(FILE *<[fp]>, fpos_t *<[pos]>); + +TRAD_SYNOPSIS + #include <stdio.h> + int fgetpos(<[fp]>, <[pos]>) + FILE *<[fp]>; + fpos_t *<[pos]>; + +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. + +You can use <<fgetpos>> to report on the current position for a file +identified by <[fp]>; <<fgetpos>> will write a value +representing that position at <<*<[pos]>>>. Later, you can +use this value with <<fsetpos>> to return the file to this +position. + +In the current implementation, <<fgetpos>> simply uses a character +count to represent the file position; this is the same number that +would be returned by <<ftell>>. + +RETURNS +<<fgetpos>> returns <<0>> when successful. If <<fgetpos>> fails, the +result is <<1>>. Failure occurs on streams that do not support +positioning; the global <<errno>> indicates this condition with the +value <<ESPIPE>>. + +PORTABILITY +<<fgetpos>> is required by the ANSI C standard, but the meaning of the +value it records is not specified beyond requiring that it be +acceptable as an argument to <<fsetpos>>. In particular, other +conforming C implementations may return a different result from +<<ftell>> than what <<fgetpos>> writes at <<*<[pos]>>>. + +No supporting OS subroutines are required. +*/ + +#include <stdio.h> + +int +_DEFUN (fgetpos, (fp, pos), + FILE * fp _AND + fpos_t * pos) +{ + *pos = ftell (fp); + + if (*pos != -1) + return 0; + return 1; +} |