Difference between revisions of "BINSEEK()"
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==Purpose== | ==Purpose== | ||
Function to position the file pointer in binary file | Function to position the file pointer in binary file | ||
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==Syntax== | ==Syntax== | ||
| − | BINSEEK( | + | BINSEEK(<expN1C>,<expN2>,<expN3>) |
| − | + | ||
==See Also== | ==See Also== | ||
[[BIN2I()]], [[BIN2L()]], [[BIN2W()]], [[BINCLOSE()]], [[BINCREATE()]], [[BINOPEN()]], [[BINREAD()]], [[BINWRITE()]], [[FSEEK()]], [[I2BIN()]], [[L2BIN()]] | [[BIN2I()]], [[BIN2L()]], [[BIN2W()]], [[BINCLOSE()]], [[BINCREATE()]], [[BINOPEN()]], [[BINREAD()]], [[BINWRITE()]], [[FSEEK()]], [[I2BIN()]], [[L2BIN()]] | ||
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==Description== | ==Description== | ||
The BINSEEK() function is used to position to a byte offset within a binary file opened with the BINCREATE() or BINOPEN() functions. The <expN1> is the file descriptor which was returned when the file was opened with either the BINCREATE() or BINOPEN() functions. The <expN2> is the byte offset to move the file pointer based on the value defined by <expN3>. The value of <expN3> represents a positioning mode that defines the position from which to start the byte offset. The positioning mode options are: | The BINSEEK() function is used to position to a byte offset within a binary file opened with the BINCREATE() or BINOPEN() functions. The <expN1> is the file descriptor which was returned when the file was opened with either the BINCREATE() or BINOPEN() functions. The <expN2> is the byte offset to move the file pointer based on the value defined by <expN3>. The value of <expN3> represents a positioning mode that defines the position from which to start the byte offset. The positioning mode options are: | ||
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!Offset||Description | !Offset||Description | ||
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The BINSEEK() function returns the new file position relative to the beginning of the file. The binary conversion functions may be used in conjunction with the binary file functions. | The BINSEEK() function returns the new file position relative to the beginning of the file. The binary conversion functions may be used in conjunction with the binary file functions. | ||
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==Example== | ==Example== | ||
<code lang="recital"> | <code lang="recital"> | ||
| − | fd = binopen("file.obj") | + | fd = binopen("file.obj", 2) |
count = binread(fd, 4) | count = binread(fd, 4) | ||
count = bin2l(count) | count = bin2l(count) | ||
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</code> | </code> | ||
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[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:Functions]] | [[Category:Functions]] | ||
| − | [[Category: | + | [[Category:Object Storage Functions]] |
| − | [[Category: | + | [[Category:Lianja VFP Extensions]] |
| + | [[Category:VFP Function Extensions]] | ||
Latest revision as of 20:55, 28 February 2019
Contents
Purpose
Function to position the file pointer in binary file
Syntax
BINSEEK(<expN1C>,<expN2>,<expN3>)
See Also
BIN2I(), BIN2L(), BIN2W(), BINCLOSE(), BINCREATE(), BINOPEN(), BINREAD(), BINWRITE(), FSEEK(), I2BIN(), L2BIN()
Description
The BINSEEK() function is used to position to a byte offset within a binary file opened with the BINCREATE() or BINOPEN() functions. The <expN1> is the file descriptor which was returned when the file was opened with either the BINCREATE() or BINOPEN() functions. The <expN2> is the byte offset to move the file pointer based on the value defined by <expN3>. The value of <expN3> represents a positioning mode that defines the position from which to start the byte offset. The positioning mode options are:
| Offset | Description |
|---|---|
| 0 | Start from the beginning of file |
| 1 | Start from the current position |
| 2 | Start from the end of file |
The BINSEEK() function returns the new file position relative to the beginning of the file. The binary conversion functions may be used in conjunction with the binary file functions.
Example
fd = binopen("file.obj", 2) count = binread(fd, 4) count = bin2l(count) count = l2bin(count + 1) binseek(fd, 512, 0) binwrite(fd, count) binclose(fd)
