GpiSetMetaFileBits
This call transfers metafile data from application storage into a memory metafile.
Syntax
GpiSetMetaFileBits(hmf, lOffset, lLength, pbBuffer)
Parameters
- hmf (HMF) - input
- Metafile-memory handle.
- lOffset (LONG) - input
- Offset, in bytes, into the metafile data from the transfer must start.
- This is used when the metafile data is too long to fit into a single application buffer. This parameter must be greater or equal to 0.
- lLength (LONG) - input
- Length of the metafile data.
- It must be greater or equal to 0.
- pbBuffer (PBYTE) - input
- Metafile data buffer.
Return Value
- rc (BOOL) - returns
- Success indicator.
- TRUE
- Successful completion
- FALSE
- Error occurred.
Remarks
The application must ensure that the data is in the correct format. It should not have been changed since it was created by GpiQueryMetaFileBits. The length of the metafile is increased, if necessary, to accommodate the supplied data. If the supplied data is shorter, the metafile length is not reduced. However, in this case the metafile is still valid, if the data in it is complete and otherwise correct.
Errors
Possible returns from WinGetLastError:
- PMERR_INV_HMF (0x207E)
- An invalid metafile handle was specified.
- PMERR_INV_METAFILE_LENGTH (0x209E)
- An invalid length parameter was specified with GpiSetMetaFileBits or GpiQueryMetaFileBits.
- PMERR_INV_METAFILE_OFFSET (0x209F)
- An invalid length parameter was specified with GpiSetMetaFileBits or GpiQueryMetaFileBits.
- PMERR_METAFILE_IN_USE (0x20D9)
- An attempt has been made to access a metafile that is in use by another thread.
Example Code
#define INCL_GPIMETAFILES /* Or use INCL_GPI, INCL_PM, */ #include <os2.h> HMF hmf; /* Metafile-memory handle. */ LONG lOffset; /* Offset, in bytes, into the metafile data from the transfer must start. */ LONG lLength; /* Length of the metafile data. */ PBYTE pbBuffer; /* Metafile data buffer. */ BOOL rc; /* Success indicator. */ rc = GpiSetMetaFileBits(hmf, lOffset, lLength, pbBuffer);
This example shows how to copy a metafile into application storage to edit the contents and then write back to the metafile using the GpiSetMetaFileBits call.
#define INCL_GPIMETAFILES
#include <OS2.H>
HPS hps; /* Presentation-space handle. */
HMF hmf;
PBYTE pbBuffer;
LONG cBytes;
LONG lOffset;
hmf = GpiLoadMetaFile(hps, "sample.met");
/* Allocate the buffer for the metafile data. */
cBytes = GpiQueryMetaFileLength(hmf);/* gets length of metafile */
DosAllocMem((PPVOID)pbBuffer, cBytes, PAG_READ | PAG_WRITE | PAG_COMMIT);
GpiQueryMetaFileBits(hmf, /* handle of metafile */
lOffset, /* offset of next byte to retrieve */
cBytes, /* retrieves cBytes */
pbBuffer); /* buffer to receive metafile data */
/* . */
/* work with the metafile */
/* . */
/* write data back to the metafile */
GpiSetMetaFileBits(hmf, lOffset, cBytes, pbBuffer);