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Diffstat (limited to 'gnulib/doc/stat-size.texi')
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| -rw-r--r-- | gnulib/doc/stat-size.texi | 25 |
2 files changed, 25 insertions, 0 deletions
diff --git a/gnulib b/gnulib deleted file mode 160000 -Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1 diff --git a/gnulib/doc/stat-size.texi b/gnulib/doc/stat-size.texi new file mode 100644 index 0000000..17b5be9 --- /dev/null +++ b/gnulib/doc/stat-size.texi @@ -0,0 +1,25 @@ +@node stat-size +@section stat-size + +The @code{stat-size} module provides a small number of macros +intended for interpreting the file size information in an instance of +@code{struct stat}. + +@c We deliberately don't document DEV_BSIZE (it looks to James +@c Youngman as if the ST_NBLOCKSIZE macro should be used instead). + +@findex ST_NBLOCKS +@findex ST_NBLOCKSIZE +@cindex block size +On POSIX systems, the @code{st_blocks} member of @code{struct stat} +contains the number of disk blocks occupied by a file. The +@code{ST_NBLOCKS} macro is used to estimate this quantity on systems +which don't actually have @code{st_blocks}. Each of these blocks +contains @code{ST_NBLOCKSIZE} bytes. + +@findex ST_BLKSIZE +The value of @code{ST_NBLOCKSIZE} is often quite small, small enough +that performing I/O in chunks that size would be inefficient. +@code{ST_BLKSIZE} is the I/O block size recommended for I/O to this +file. This is not guaranteed to give optimum performance, but it +should be reasonably efficient. |