diff options
Diffstat (limited to 'doc/comboot.txt')
| -rw-r--r-- | doc/comboot.txt | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/doc/comboot.txt b/doc/comboot.txt index c4b0f076..42078ed5 100644 --- a/doc/comboot.txt +++ b/doc/comboot.txt @@ -293,7 +293,7 @@ AX=0006h [2.08] Open file Input: AX 0006h ES:SI null-terminated filename Output: SI file handle - EAX length of file in bytes + EAX length of file in bytes, or -1 CX file block size Open a file for reading. The exact syntax of the filenames @@ -304,6 +304,9 @@ AX=0006h [2.08] Open file Note: SYSLINUX considers a zero-length file to be nonexistent. + In 3.70 or later, EAX can contain -1 indicating that the file + length is unknown. + AX=0007h [2.08] Read file @@ -312,6 +315,7 @@ AX=0007h [2.08] Read file ES:BX buffer CX number of blocks to read Output: SI file handle, or 0 if EOF was reached + ECX number of bytes read [3.70] Read blocks from a file. Note that the file handle that is returned in SI may not be the same value that was passed in. @@ -319,6 +323,10 @@ AX=0007h [2.08] Read file If end of file was reached (SI=0), the file was automatically closed. + In 3.70 or later, ECX returns the number of bytes read. This + will always be a multiple of the block size unless EOF is + reached. + The address of the buffer (ES:BX) should be at least 512-byte aligned. SYSLINUX guarantees at least this alignment for the COMBOOT load segment or the COM32 bounce buffer. |