summaryrefslogtreecommitdiffstats
path: root/HDF5Examples/C/H5T/h5ex_t_stringatt.c
diff options
context:
space:
mode:
authorAllen Byrne <50328838+byrnHDF@users.noreply.github.com>2023-11-27 21:30:15 (GMT)
committerGitHub <noreply@github.com>2023-11-27 21:30:15 (GMT)
commitfc88fcde1091cf12c1e88c783a14ee0f1cffe31c (patch)
tree91b88b62cd30ed37ee9227e43989e95035be43c3 /HDF5Examples/C/H5T/h5ex_t_stringatt.c
parenta067bf71f57723d2dfca7dfe2ffd9ea502eccd4f (diff)
downloadhdf5-fc88fcde1091cf12c1e88c783a14ee0f1cffe31c.zip
hdf5-fc88fcde1091cf12c1e88c783a14ee0f1cffe31c.tar.gz
hdf5-fc88fcde1091cf12c1e88c783a14ee0f1cffe31c.tar.bz2
Develop merge examples (#3851)
* Merge examples repo into library * Change grepTest to be more fault-tolerant * Update examples macro file * Exclude all Fortran examples from doxygen
Diffstat (limited to 'HDF5Examples/C/H5T/h5ex_t_stringatt.c')
-rw-r--r--HDF5Examples/C/H5T/h5ex_t_stringatt.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/HDF5Examples/C/H5T/h5ex_t_stringatt.c b/HDF5Examples/C/H5T/h5ex_t_stringatt.c
new file mode 100644
index 0000000..26e86d2
--- /dev/null
+++ b/HDF5Examples/C/H5T/h5ex_t_stringatt.c
@@ -0,0 +1,155 @@
+/************************************************************
+
+ This example shows how to read and write string datatypes
+ to an attribute. The program first writes strings to an
+ attribute with a dataspace of DIM0, then closes the file.
+ Next, it reopens the file, reads back the data, and
+ outputs it to the screen.
+
+ This file is intended for use with HDF5 Library version 1.8
+
+ ************************************************************/
+
+#include "hdf5.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+#define FILE "h5ex_t_stringatt.h5"
+#define DATASET "DS1"
+#define ATTRIBUTE "A1"
+#define DIM0 4
+#define SDIM 8
+
+int
+main(void)
+{
+ hid_t file, filetype, memtype, space, dset, attr;
+ /* Handles */
+ herr_t status;
+ hsize_t dims[1] = {DIM0};
+ size_t sdim;
+ char wdata[DIM0][SDIM] = {"Parting", "is such", "sweet", "sorrow."},
+ /* Write buffer */
+ **rdata; /* Read buffer */
+ int ndims, i;
+
+ /*
+ * Create a new file using the default properties.
+ */
+ file = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+ /*
+ * Create file and memory datatypes. For this example we will save
+ * the strings as FORTRAN strings, therefore they do not need space
+ * for the null terminator in the file.
+ */
+ filetype = H5Tcopy(H5T_FORTRAN_S1);
+ status = H5Tset_size(filetype, SDIM - 1);
+ memtype = H5Tcopy(H5T_C_S1);
+ status = H5Tset_size(memtype, SDIM);
+
+ /*
+ * Create dataset with a null dataspace.
+ */
+ space = H5Screate(H5S_NULL);
+ dset = H5Dcreate(file, DATASET, H5T_STD_I32LE, space, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+ status = H5Sclose(space);
+
+ /*
+ * Create dataspace. Setting maximum size to NULL sets the maximum
+ * size to be the current size.
+ */
+ space = H5Screate_simple(1, dims, NULL);
+
+ /*
+ * Create the attribute and write the string data to it.
+ */
+ attr = H5Acreate(dset, ATTRIBUTE, filetype, space, H5P_DEFAULT, H5P_DEFAULT);
+ status = H5Awrite(attr, memtype, wdata[0]);
+
+ /*
+ * Close and release resources.
+ */
+ status = H5Aclose(attr);
+ status = H5Dclose(dset);
+ status = H5Sclose(space);
+ status = H5Tclose(filetype);
+ status = H5Tclose(memtype);
+ status = H5Fclose(file);
+
+ /*
+ * Now we begin the read section of this example. Here we assume
+ * the attribute and string have the same name and rank, but can
+ * have any size. Therefore we must allocate a new array to read
+ * in data using malloc().
+ */
+
+ /*
+ * Open file, dataset, and attribute.
+ */
+ file = H5Fopen(FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
+ dset = H5Dopen(file, DATASET, H5P_DEFAULT);
+ attr = H5Aopen(dset, ATTRIBUTE, H5P_DEFAULT);
+
+ /*
+ * Get the datatype and its size.
+ */
+ filetype = H5Aget_type(attr);
+ sdim = H5Tget_size(filetype);
+ sdim++; /* Make room for null terminator */
+
+ /*
+ * Get dataspace and allocate memory for read buffer. This is a
+ * two dimensional attribute so the dynamic allocation must be done
+ * in steps.
+ */
+ space = H5Aget_space(attr);
+ ndims = H5Sget_simple_extent_dims(space, dims, NULL);
+
+ /*
+ * Allocate array of pointers to rows.
+ */
+ rdata = (char **)malloc(dims[0] * sizeof(char *));
+
+ /*
+ * Allocate space for integer data.
+ */
+ rdata[0] = (char *)malloc(dims[0] * sdim * sizeof(char));
+
+ /*
+ * Set the rest of the pointers to rows to the correct addresses.
+ */
+ for (i = 1; i < dims[0]; i++)
+ rdata[i] = rdata[0] + i * sdim;
+
+ /*
+ * Create the memory datatype.
+ */
+ memtype = H5Tcopy(H5T_C_S1);
+ status = H5Tset_size(memtype, sdim);
+
+ /*
+ * Read the data.
+ */
+ status = H5Aread(attr, memtype, rdata[0]);
+
+ /*
+ * Output the data to the screen.
+ */
+ for (i = 0; i < dims[0]; i++)
+ printf("%s[%d]: %s\n", ATTRIBUTE, i, rdata[i]);
+
+ /*
+ * Close and release resources.
+ */
+ free(rdata[0]);
+ free(rdata);
+ status = H5Aclose(attr);
+ status = H5Dclose(dset);
+ status = H5Sclose(space);
+ status = H5Tclose(filetype);
+ status = H5Tclose(memtype);
+ status = H5Fclose(file);
+
+ return 0;
+}