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-rw-r--r--newlib/libc/stdio/fsetpos.c54
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 00000000000..28cd69eadb4
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+++ b/newlib/libc/stdio/fsetpos.c
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+/*
+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;
+}