> For the complete documentation index, see [llms.txt](https://docs.hex-rays.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hex-rays.com/8.4/developer-guide/idc/idc-api-reference/alphabetical-list-of-idc-functions/299.md).

# add\_segm\_ex

```
Create a new segment
     startea  - linear address of the start of the segment
     endea    - linear address of the end of the segment
                this address will not belong to the segment
                'endea' should be higher than 'startea'
     base     - base paragraph or selector of the segment.
                a paragraph is 16byte memory chunk.
                If a selector value is specified, the selector should be
                already defined.
     use32    - 0: 16bit segment, 1: 32bit segment, 2: 64bit segment
     align    - segment alignment. see below for alignment values
     comb     - segment combination. see below for combination values.
     flags    - combination of ADDSEG_... bits
returns: 0-failed, 1-ok

success add_segm_ex(long startea, long endea, long sel, long use32, long align, long comb, long flags);

#define ADDSEG_NOSREG   0x0001  // set all default segment register values
                                // to BADSELs
                                // (undefine all default segment registers)
#define ADDSEG_OR_DIE   0x0002  // qexit() if can't add a segment
#define ADDSEG_NOTRUNC  0x0004  // don't truncate the new segment at the beginning
                                // of the next segment if they overlap.
                                // destroy/truncate old segments instead.
#define ADDSEG_QUIET    0x0008  // silent mode, no "Adding segment..." in the messages window
#define ADDSEG_FILLGAP  0x0010  // If there is a gap between the new segment
                                // and the previous one, and this gap is less
                                // than 64K, then fill the gap by extending the
                                // previous segment and adding .align directive
                                // to it. This way we avoid gaps between segments.
                                // Too many gaps lead to a virtual array failure.
                                // It cannot hold more than ~1000 gaps.
#define ADDSEG_SPARSE   0x0020  // Use sparse storage method for the new segment
```


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