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Diffstat (limited to 'newlib/libc/stdio/fsetpos.c')
-rw-r--r-- | newlib/libc/stdio/fsetpos.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/newlib/libc/stdio/fsetpos.c b/newlib/libc/stdio/fsetpos.c new file mode 100644 index 0000000..28cd69e --- /dev/null +++ b/newlib/libc/stdio/fsetpos.c @@ -0,0 +1,54 @@ +/* +FUNCTION +<<fsetpos>>---restore position of a stream or file + +INDEX + fsetpos + +ANSI_SYNOPSIS + #include <stdio.h> + int fsetpos(FILE *<[fp]>, const fpos_t *<[pos]>); + +TRAD_SYNOPSIS + #include <stdio.h> + int fsetpos(<[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 <<fsetpos>> to return the file identified by <[fp]> to a previous +position <<*<[pos]>>> (after first recording it with <<fgetpos>>). + +See <<fseek>> for a similar facility. + +RETURNS +<<fgetpos>> returns <<0>> when successful. If <<fgetpos>> fails, the +result is <<1>>. The reason for failure is indicated in <<errno>>: +either <<ESPIPE>> (the stream identified by <[fp]> doesn't support +repositioning) or <<EINVAL>> (invalid file position). + +PORTABILITY +ANSI C requires <<fsetpos>>, but does not specify the nature of +<<*<[pos]>>> beyond identifying it as written by <<fgetpos>>. + +Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>, +<<lseek>>, <<read>>, <<sbrk>>, <<write>>. +*/ + +#include <stdio.h> + +int +_DEFUN (fsetpos, (iop, pos), + FILE * iop _AND + _CONST fpos_t * pos) +{ + int x = fseek (iop, *pos, SEEK_SET); + + if (x != 0) + return 1; + return 0; +} |