fread

fread reads data from a file.

dat = fread(fh, ssType)

dat = fread(fh, ssType, n)

dat = fread_char(fh, n)

dat = fread_char8(fh, n)

dat = fread_float64(fh, n)

dat = fread_float32(fh, n)

dat = fread_int8(fh, n)

dat = fread_uint8(fh, n)

dat = fread_int16(fh, n)

dat = fread_uint16(fh, n)

dat = fread_int32(fh, n)

dat = fread_uint32(fh, n)

dat = fread_int64(fh, n)

dat = fread_uint64(fh, n)

Return Value

dat is a scalar string, if ssType is “char” or in all other cases a real vector.

Parameters

fh

Identifies the file.

ssType

ssType is one of the following strings:

Value	Old Name	Meaning
“float64”	“double”	8 Bytes floating point value, fread_float64.
“float32”	“float”	(4 Bytes)
-	“real48”	(6 Bytes)
“char”	“char”	2 Bytes-Unicode character, fread_char.
“char8”	“char8”	1 Byte, fread_char8, see also mem_get.
“int8”	-	(1 Byte)
“uint8”	“uchar”	(1 Byte)
“int16”	“short”	(2 Bytes)
“uint16”	“ushort”	(2 Bytes)
“int32”	“int, long”	(4 Bytes)
“uint32”	“uint, ulong”	(4 Bytes)
“int64”	-	(8 Bytes)
“uint64”	-	(8 Bytes)

n

n defines the number of data objects to be read. If n is not specified (or if n <= 0) the complete file will be read beginning at the current position.

Example

fh = fopen("/test.bin", "wb");
rvValues = 1:100;              // 1,2,3,4,...
fwrite(fh, "short", rvValues); // writes 100 short values
fclose(fh);
fh = fopen("/test.bin", "rb");
rvValues = fread(fh, "short", 100); // reads 100 short
fclose(fh);                         // values

History

Version	Description
5.8.2	New type “char8”.
4.2.0	If ssType == “char” is true the result string will not be truncated at the first 0-character. The strtrim function can be used to truncate the string at the first 0-character.

See also

Overview Binary and Text Files, fopen, fwrite, fseek, feof

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