dasdseq(1)

✨ dasdseq(1) — Hercules DSORG=PS retrieval command ✨

okay so bestie, welcome to the dasdseq(1) page from the General Commands Manual 💖 this is the little Hercules command that goes and fetches a DSORG=PS (sequential) dataset off a CKD/CCKD DASD for you. no cap.

the vibe is: the dataset is presumed to be encoded in EBCDIC (iykyk), and there's a second form of the command for the 'expert mode' girlies who want more advanced access to the data on the DASD image. it's giving power user energy fr fr 👑

---

🌈 SYNOPSIS

dasdseq [options...] image [sf=shadow] filespec
dasdseq [-debug] [-expert] [-ascii] image [sf=shadow] [attr] filespec
[debugopts] [ascii]

---

🦋 DESCRIPTION

so like, this is a Hercules command whose whole job is to retrieve a DSORG=PS (sequential) dataset from CKD/CCKD DASD. the dataset is presumed to be encoded in EBCDIC. periodt.

the second form of the command? that one's for 'expert mode' users, and it allows more advanced access to data on the DASD image. main character energy only 💅

---

🎀 OPTIONS

the following options are used to specify dasdseq behavior. surround each option by blank(s) — yes literally, blanks, don't skip this part bestie. the options are divided into three categories: required, optional, and expert mode operands.

🍓 Required operands

• image — specifies the Hercules CKD/CCKD DASD filename (sometimes referred to as the DASD image file) 💾
• filespec — the dataset name of the file to retrieve. it's case insensitive, and it gets converted to upper case for searching the VTOC on the image DASD volume.

🌸 Optional operands

• sf=shadow — for CCKD images which also use shadow files, this specifies the [path/]filename of the shadow file. note the sf=, which must be present for this option 🫶
• -ascii — convert the output file to ASCII (from EBCDIC). additionally, trailing blanks are trimmed. the 'ascii' option (no leading dash) is deprecated, and may be removed in a future release. so like, use the dash version, she's the icon 💅

💜 Expert mode operands

all expert mode operands are considered to be experimental. proceed accordingly bestie 😭

 dasdseq [-debug] [-expert] [-ascii] image [sf=shadow] [attr] filespec
[debugopts]

• -debug — additional debug options are displayed. specifying -debug will (eventually) display dataset extent information. (eventually!! she's on her own timeline, we respect it ✨)
• attr — dataset attributes (only useful with -abs)

[-recfm fb] [-lrecl aa]

• -recfm designates RECFM, reserved for future support
  • fb — fixed, blocked (only RECFM currently supported)
• -lrecl designates dataset LRECL
  • aa — decimal logical record length (default 80)

blocksize need not be specified; dasdseq handles whatever block size comes off the volume. she's flexible like that 💁

• filespec — composed of the following sub-operands, in the following order: heads, abs, filename.
  • -heads xx — defines # tracks per cylinder on device; xx = decimal number of heads per cylinder on device
  • -abs cc hh tt [...] [-abs cc hh tt] — -abs indicates the beginning of each extent's location in terms of absolute dasd image location.
    • cc — decimal cylinder number (relative zero)
    • hh — decimal head number (relative zero)
    • tt — decimal number of tracks in extent

when -abs is specified, each -abs group specifies one dataset extent. for multi-extent datasets, -abs groups may be repeated as needed, in the order in which the dataset's extents occur. a maximum of 123 extents are supported. with -abs, no VTOC structure is implied; a F1 DSCB will not be sought.

dasdseq will frequently report 'track not found in extent table' (along with a message from fbcopy about rc -1 from convert_tt) due to potentially missing EOF markers in the extent, and the fact that the F1 DSCB DS1LSTAR field is not valid. check your output file before you panic. 😭

fbcopy -abs ignores EOF, in case you are attempting to recovery PDS member(s) from a damaged dasd volume, preferring to wait until all tracks in the extent have been processed. tracks containing PDS members may have more than one EOF per track. expect a lot of associated manual effort with -abs. lowkey a whole project bestie 💀

when -abs is -not- specified, filename specifies the MVS DSORG=PS dataset on the volume. the dasd image volume containing the dataset must have a valid VTOC structure, and a F1 DSCB describing the dataset.

• filename — will be the filename of the output file in the current directory; output filename in the same case as the command line filename. so like, she matches your energy exactly 🎀
• debugopts — produces debugging output, refer to the source code. (yes really, go read the source, that's the citation 💅)

verbose [x [y [z]]]

• verbose — debug output level (default = 0 when not specified). higher numbers produce more output.
• x — main program (default = 1 when verbose specified)
• y — copyfile + showf1
• z — dasdutil

---

🌈 SEE ALSO

• dasdpdsu for DSORG=PO datasets
• cckd(4) for CCKD DASD
• http://www.hercules-390.org/cckddasd.html which describes the Hercules CCKD DASD facility.
• http://www.hercules-390.org/ the Hercules emulator homepage.

---

👑 HISTORY

2003-03-10 — originally written by James M. Morrison

---

and that's the whole page bestie 🫶 this one lives in the General Commands Manual and it's dated 2003-03-10, so she's been iconic since way before any of us were on the timeline. slay, honestly 💖✨🎀🦋