Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Full samples of deblocking BPAM directory blocks with code? Which program? I don't see any examples in the P/G you linked to either. What am I missing? Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of David Crayford Sent: Tuesday, May 01, 2012 8:20 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? The book also has examples and you will find full samples in the SCBCSAMP data set. http://publib.boulder.ibm.com/infocenter/zvm/v5r4/index.jsp?topic=/com.ibm.z os.r9.cbcpx01/cbcpg18096.htm On 2/05/2012 9:58 AM, Charles Mills wrote: Thanks! Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Bernd Oppolzer Sent: Tuesday, May 01, 2012 6:09 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? Thank you! Here is an excerpt of a C program which reads a directory of a PDS and inserts the member names into an AVL tree (the insert is not shown, it is done by a function call - see below). -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
My link was bad! Seems I didn't quite understand how to copy a link in Infocenter! http://publib.boulder.ibm.com/infocenter/zvm/v5r4/topic/com.ibm.zos.r9.cbcpx01/cbcpg180781.htm#wq1935 On 3/05/2012 1:09 AM, Charles Mills wrote: Full samples of deblocking BPAM directory blocks with code? Which program? I don't see any examples in the P/G you linked to either. What am I missing? Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of David Crayford Sent: Tuesday, May 01, 2012 8:20 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? The book also has examples and you will find full samples in the SCBCSAMP data set. http://publib.boulder.ibm.com/infocenter/zvm/v5r4/index.jsp?topic=/com.ibm.z os.r9.cbcpx01/cbcpg18096.htm On 2/05/2012 9:58 AM, Charles Mills wrote: Thanks! Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Bernd Oppolzer Sent: Tuesday, May 01, 2012 6:09 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? Thank you! Here is an excerpt of a C program which reads a directory of a PDS and inserts the member names into an AVL tree (the insert is not shown, it is done by a function call - see below). -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Aha! Muchas gracias! Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of David Crayford Sent: Wednesday, May 02, 2012 7:37 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? My link was bad! Seems I didn't quite understand how to copy a link in Infocenter! http://publib.boulder.ibm.com/infocenter/zvm/v5r4/topic/com.ibm.zos.r9.cbcpx 01/cbcpg180781.htm#wq1935 On 3/05/2012 1:09 AM, Charles Mills wrote: Full samples of deblocking BPAM directory blocks with code? Which program? I don't see any examples in the P/G you linked to either. What am I missing? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
On Mon, 30 Apr 2012 13:20:48 -0700, Charles Mills wrote: At least too many OPEN's is better than too many DYNALLOC's *and* too many OPEN's. Ummm. No. A few years ago, I had an APAR created because the z/OS UNIX (USS) command e.g.: $ cp -P'SPACE=(5000,5000)' homelog //temp.test.space3 cp: FSUM6260 write error on file //temp.test.space3: EDC5092I An I/O abend was trapped. $ ls -l homelog -rw-r--r-- 1 user group 346153 Jan 12 14:05 homelog was failing with a Sx37, regardless of how large an extent I requested. IBM's explanation: o If the programmer specified SPACE, the C/LE RTL assumed a RLSE subparameter. (This seems precisely backward to me. If the RTL supplies a generous default, RLSE may be appropriate. If the programmer specified SPACE explicitly, give him what he asks for.) o The command internally caused the data set to be opened and closed _four_ times (!?!?!?!). After the first close, most of the space was released. The attempt to write the actual data was bound to fail writing to a minimal extent. IBM's reactions were: o Specify a secondary extent. o FIN. o For compatibility, we'll retain the current behavior, but provide the programmer a NORLSE option. The problem persists at z/OS 1.12: D37-04,IFG0554P,user,STEP1,SYS00017,41CA,TSO026,user.TEMP.TEST.SPACE3 There seems to be no NORLSE option. If I supply a secondary extent, I get an 8 block (1 track?) primary extent and a 4008 block second extent. SIGH/ I can't respect this. Does any IBM representative dare to comment on it? -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
On Mon, 30 Apr 2012 23:43:24 +0200, Bernd Oppolzer wrote: Don't know what it's worth, but I'm quite sure that you can read a directory of a PDS simply by issuing fopen on it as a binary file - like this directory = fopen (dd:pdsfile, rb); that is, if you don't specify member names in parantheses, you get the directory of the PDS. Rexx, for example, doesn't work quite that way. The open fails unless the programmer specifies DSORG(PS) at allocation. And, yes, if you specify dd:dsname on fopen, there will be no DYNALLOC etc. and no SYSx ddnames, because there is already a ddname. FTP, for another example, doesn't work quite that way. Overriding attributes at allocation will sometimes be ignored and attributes from the DSCB used regardless. TSO TRANSMIT, for YA example doesn't work that way. If I allocate DATA.SET.NAME(MEMBER), which is a sequential allocation, and pass the ddname as INDD to TRANSMIT, it is transmitted as an IEBCOPY unloaded PDS member. I don't know for any of these cases whether the utility uses the argument DDNAME after tweaking the JFCB, or performs a DYNALLOC. -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
The point here is not what some particular routine oor utility may do or permit. It is what can be done ab initio by an programmer who wants to do it using the HLASM or some particular SLPL . z/OS MVS does permit one to open a PDS as a PS data set in a routine written in assembly language or PL/I, and what one then gets with successive reads are its successive directory blocks. I have done this many times without incident, but I do not of course recommend it to novices. I have not myself done it in C; but Bernd Oppolzer is a careful, highly reliable reporter of his experience; and I am thus sure that it can be done in C too. John Gilmore, Ashland, MA 01721 - USA -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Thank you!
Here is an excerpt of a C program which reads a directory of a PDS
and inserts the member names into an AVL tree (the insert is not shown,
it is done by a function call - see below).
Kind regards
Bernd
static int lese_memberliste (char *parm_infile,
baumMEMknoten **pres)
//
/* Funktion zum Lesen einer Memberliste */
/* einer PO-Datei; die Membernamen werden */
/* in einen AVL-Baum eingetragen */
//
{
FILE *direct;
char buf [256];
int x;
char *cp;
int laenge;
unsigned long ttrc;
int ttr;
int anz_bytes;
int eof;
int rc = 0;
char mem_high [8];
baumMEMknoten *proot = NULL;
baumMEMknoten *pneu;
int hchanged;
membname m;
eof = 0;
memset (mem_high, 0xff, 8);
//
/* raus, wenn Directory nicht aufgeht */
//
direct = fopen (parm_infile, rb);
if (direct == NULL)
RETURN_VALUE 8;
for (;;)
{
//
/* naechsten Directory-Block einlesen */
//
memset (buf, 0x00, 256);
x = fread (buf, 1, 256, direct);
if (x == 0)
break;
#ifdef TEST
printf ([cp2970] \n);
printf ([cp2970] Rueckgabe von fread = %d\n, x);
printf ([cp2970] \n);
dump (buf, buf + x - 1, stdout);
#endif
cp = buf + 2;
laenge = *((short *) buf) - 2;
while (laenge 0)
{
//
/* naehere Info hierzu in den IBM-Brosch. */
/* zum Aufbau der PO-Directories. */
//
if (memcmp (cp, mem_high, 8) == 0)
{
eof = 1;
break;
}
//
/* Laenge des Eintrags in Halbworten steht*/
/* in den Bits 3 bis 7 des TTRC-Wortes*/
//
ttrc = *((unsigned long *) (cp + 8));
ttr = ttrc 8;
anz_bytes = (ttrc 0x1f) * 2;
#ifdef TEST
printf ([cp2970] Member %-8.8s TTR %06X Laenge/Bytes %d\n,
cp, ttr, anz_bytes);
#endif
if (memcmp (cp, ED, 2) == 0)
{
memcpy (m.name, cp, 8);
hchanged = 0;
pneu = baumMEMsuche (m, proot, hchanged, 1);
pneu - obj = atoi (cp + 2);
}
cp += (anz_bytes + 12);
laenge -= (anz_bytes + 12);
}
if (eof)
break;
}
fclose (direct);
*pres = proot;
RETURN_VALUE rc;
}
Am 01.05.2012 23:52, schrieb John Gilmore:
The point here is not what some particular routine oor utility may do
or permit. It is what can be done ab initio by an programmer who
wants to do it using the HLASM or some particular SLPL .
z/OS MVS does permit one to open a PDS as a PS data set in a routine
written in assembly language or PL/I, and what one then gets with
successive reads are its successive directory blocks.
I have done this many times without incident, but I do not of course
recommend it to novices.
I have not myself done it in C; but Bernd Oppolzer is a careful,
highly reliable reporter of his experience; and I am thus sure that it
can be done in C too.
John Gilmore, Ashland, MA 01721 - USA
--
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
--
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send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Thanks!
Charles
-Original Message-
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf
Of Bernd Oppolzer
Sent: Tuesday, May 01, 2012 6:09 PM
To: IBM-MAIN@bama.ua.edu
Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Thank you!
Here is an excerpt of a C program which reads a directory of a PDS and
inserts the member names into an AVL tree (the insert is not shown, it is
done by a function call - see below).
Kind regards
Bernd
static int lese_memberliste (char *parm_infile,
baumMEMknoten **pres)
//
/* Funktion zum Lesen einer Memberliste */
/* einer PO-Datei; die Membernamen werden */
/* in einen AVL-Baum eingetragen */
//
{
FILE *direct;
char buf [256];
int x;
char *cp;
int laenge;
unsigned long ttrc;
int ttr;
int anz_bytes;
int eof;
int rc = 0;
char mem_high [8];
baumMEMknoten *proot = NULL;
baumMEMknoten *pneu;
int hchanged;
membname m;
eof = 0;
memset (mem_high, 0xff, 8);
//
/* raus, wenn Directory nicht aufgeht */
//
direct = fopen (parm_infile, rb);
if (direct == NULL)
RETURN_VALUE 8;
for (;;)
{
//
/* naechsten Directory-Block einlesen */
//
memset (buf, 0x00, 256);
x = fread (buf, 1, 256, direct);
if (x == 0)
break;
#ifdef TEST
printf ([cp2970] \n);
printf ([cp2970] Rueckgabe von fread = %d\n, x);
printf ([cp2970] \n);
dump (buf, buf + x - 1, stdout);
#endif
cp = buf + 2;
laenge = *((short *) buf) - 2;
while (laenge 0)
{
//
/* naehere Info hierzu in den IBM-Brosch. */
/* zum Aufbau der PO-Directories. */
//
if (memcmp (cp, mem_high, 8) == 0)
{
eof = 1;
break;
}
//
/* Laenge des Eintrags in Halbworten steht*/
/* in den Bits 3 bis 7 des TTRC-Wortes*/
//
ttrc = *((unsigned long *) (cp + 8));
ttr = ttrc 8;
anz_bytes = (ttrc 0x1f) * 2;
#ifdef TEST
printf ([cp2970] Member %-8.8s TTR %06X Laenge/Bytes %d\n,
cp, ttr, anz_bytes);
#endif
if (memcmp (cp, ED, 2) == 0)
{
memcpy (m.name, cp, 8);
hchanged = 0;
pneu = baumMEMsuche (m, proot, hchanged, 1);
pneu - obj = atoi (cp + 2);
}
cp += (anz_bytes + 12);
laenge -= (anz_bytes + 12);
}
if (eof)
break;
}
fclose (direct);
*pres = proot;
RETURN_VALUE rc;
}
Am 01.05.2012 23:52, schrieb John Gilmore:
The point here is not what some particular routine oor utility may do
or permit. It is what can be done ab initio by an programmer who
wants to do it using the HLASM or some particular SLPL .
z/OS MVS does permit one to open a PDS as a PS data set in a routine
written in assembly language or PL/I, and what one then gets with
successive reads are its successive directory blocks.
I have done this many times without incident, but I do not of course
recommend it to novices.
I have not myself done it in C; but Bernd Oppolzer is a careful,
highly reliable reporter of his experience; and I am thus sure that it
can be done in C too.
John Gilmore, Ashland, MA 01721 - USA
--
For IBM-MAIN subscribe / signoff / archive access instructions, send
email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
--
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to lists...@bama.ua.edu with the message: INFO IBM-MAIN
--
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send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
The book also has examples and you will find full samples in the
SCBCSAMP data set.
http://publib.boulder.ibm.com/infocenter/zvm/v5r4/index.jsp?topic=/com.ibm.zos.r9.cbcpx01/cbcpg18096.htm
On 2/05/2012 9:58 AM, Charles Mills wrote:
Thanks!
Charles
-Original Message-
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf
Of Bernd Oppolzer
Sent: Tuesday, May 01, 2012 6:09 PM
To: IBM-MAIN@bama.ua.edu
Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Thank you!
Here is an excerpt of a C program which reads a directory of a PDS and
inserts the member names into an AVL tree (the insert is not shown, it is
done by a function call - see below).
Kind regards
Bernd
static int lese_memberliste (char *parm_infile,
baumMEMknoten **pres)
//
/* Funktion zum Lesen einer Memberliste */
/* einer PO-Datei; die Membernamen werden */
/* in einen AVL-Baum eingetragen */
//
{
FILE *direct;
char buf [256];
int x;
char *cp;
int laenge;
unsigned long ttrc;
int ttr;
int anz_bytes;
int eof;
int rc = 0;
char mem_high [8];
baumMEMknoten *proot = NULL;
baumMEMknoten *pneu;
int hchanged;
membname m;
eof = 0;
memset (mem_high, 0xff, 8);
//
/* raus, wenn Directory nicht aufgeht */
//
direct = fopen (parm_infile, rb);
if (direct == NULL)
RETURN_VALUE 8;
for (;;)
{
//
/* naechsten Directory-Block einlesen */
//
memset (buf, 0x00, 256);
x = fread (buf, 1, 256, direct);
if (x == 0)
break;
#ifdef TEST
printf ([cp2970] \n);
printf ([cp2970] Rueckgabe von fread = %d\n, x);
printf ([cp2970] \n);
dump (buf, buf + x - 1, stdout);
#endif
cp = buf + 2;
laenge = *((short *) buf) - 2;
while (laenge 0)
{
//
/* naehere Info hierzu in den IBM-Brosch. */
/* zum Aufbau der PO-Directories. */
//
if (memcmp (cp, mem_high, 8) == 0)
{
eof = 1;
break;
}
//
/* Laenge des Eintrags in Halbworten steht*/
/* in den Bits 3 bis 7 des TTRC-Wortes*/
//
ttrc = *((unsigned long *) (cp + 8));
ttr = ttrc 8;
anz_bytes = (ttrc 0x1f) * 2;
#ifdef TEST
printf ([cp2970] Member %-8.8s TTR %06X Laenge/Bytes %d\n,
cp, ttr, anz_bytes);
#endif
if (memcmp (cp, ED, 2) == 0)
{
memcpy (m.name, cp, 8);
hchanged = 0;
pneu = baumMEMsuche (m,proot,hchanged, 1);
pneu - obj = atoi (cp + 2);
}
cp += (anz_bytes + 12);
laenge -= (anz_bytes + 12);
}
if (eof)
break;
}
fclose (direct);
*pres = proot;
RETURN_VALUE rc;
}
Am 01.05.2012 23:52, schrieb John Gilmore:
The point here is not what some particular routine oor utility may do
or permit. It is what can be done ab initio by an programmer who
wants to do it using the HLASM or some particular SLPL .
z/OS MVS does permit one to open a PDS as a PS data set in a routine
written in assembly language or PL/I, and what one then gets with
successive reads are its successive directory blocks.
I have done this many times without incident, but I do not of course
recommend it to novices.
I have not myself done it in C; but Bernd Oppolzer is a careful,
highly reliable reporter of his experience; and I am thus sure that it
can be done in C too.
John Gilmore, Ashland, MA 01721 - USA
--
For IBM-MAIN subscribe / signoff / archive access instructions, send
email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
--
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to lists...@bama.ua.edu with the message: INFO IBM-MAIN
--
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send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
--
For IBM-MAIN
Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Does anyone *know* whether a C/C++ Language Environment fopen() of a filename of the form DD:ddname(member) use an OPEN of ddname followed by a BLDL or FIND for member (the way any reasonable programmer would) or does it do a whole new DYNALLOC for dsname(member)? (Seems like a dumb question, but FTP does it that way, so stranger things have happened.) My *interpretation* of the allocation messages - I don't see allocate and de-allocate messages for a SYSn that appears to be for member - leads me to believe that C/C++ LE does it right. But I could be reading it wrong. Does anyone *know*? Thanks, Charles -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Charles, I'm nearly certain that it doesn't do a SVC99 when you are using fopen with a DDNAME But it does seem to do a OPEN/BLDL/POINTSTOW/CLOSEfor each fopen() / fclose() using //DD:MYDD(MEM) IMO, there are a couple of important missing things: 1) There isn't a way to update (or get) the PDS directory user data when processing the member with fopen()/fclose(). 2) You would really like to be able to do this: fopen(//DD:MYDD(MEM1), ...) freopen(//DD:MYDD(MEM2), ) so that the freopen() caused a STOW (if opened update) and a BLDL/POINT, and avoided the cost of a complete OPEN/CLOSE path.I don't think that it does that. So, for my money, better BPAM support would be nice. Kirk Wolf Dovetailed Technologies http://dovetail.com On Mon, Apr 30, 2012 at 11:45 AM, Charles Mills charl...@mcn.org wrote: Does anyone *know* whether a C/C++ Language Environment fopen() of a filename of the form DD:ddname(member) use an OPEN of ddname followed by a BLDL or FIND for member (the way any reasonable programmer would) or does it do a whole new DYNALLOC for dsname(member)? (Seems like a dumb question, but FTP does it that way, so stranger things have happened.) My *interpretation* of the allocation messages - I don't see allocate and de-allocate messages for a SYSn that appears to be for member - leads me to believe that C/C++ LE does it right. But I could be reading it wrong. Does anyone *know*? Thanks, Charles -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Thanks! At least too many OPEN's is better than too many DYNALLOC's *and* too many OPEN's. There isn't a way to update (or get) the PDS directory user data Not a huge deal to write your own BPAM library, but I agree. When I first came to z/OS C/C++ about two years ago I was surprised that there were not more z/OS-specific library routines (or z/OS-specific enhancements to the inherited-from-UNIX library routines). Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Kirk Wolf Sent: Monday, April 30, 2012 11:11 AM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? Charles, I'm nearly certain that it doesn't do a SVC99 when you are using fopen with a DDNAME But it does seem to do a OPEN/BLDL/POINTSTOW/CLOSEfor each fopen() / fclose() using //DD:MYDD(MEM) IMO, there are a couple of important missing things: 1) There isn't a way to update (or get) the PDS directory user data when processing the member with fopen()/fclose(). 2) You would really like to be able to do this: fopen(//DD:MYDD(MEM1), ...) freopen(//DD:MYDD(MEM2), ) so that the freopen() caused a STOW (if opened update) and a BLDL/POINT, and avoided the cost of a complete OPEN/CLOSE path.I don't think that it does that. So, for my money, better BPAM support would be nice. Kirk Wolf Dovetailed Technologies http://dovetail.com On Mon, Apr 30, 2012 at 11:45 AM, Charles Mills charl...@mcn.org wrote: Does anyone *know* whether a C/C++ Language Environment fopen() of a filename of the form DD:ddname(member) use an OPEN of ddname followed by a BLDL or FIND for member (the way any reasonable programmer would) or does it do a whole new DYNALLOC for dsname(member)? (Seems like a dumb question, but FTP does it that way, so stranger things have happened.) My *interpretation* of the allocation messages - I don't see allocate and de-allocate messages for a SYSn that appears to be for member - leads me to believe that C/C++ LE does it right. But I could be reading it wrong. Does anyone *know*? Thanks, Charles -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND?
Don't know what it's worth, but I'm quite sure that you can read a directory of a PDS simply by issuing fopen on it as a binary file - like this directory = fopen (dd:pdsfile, rb); that is, if you don't specify member names in parantheses, you get the directory of the PDS. And, yes, if you specify dd:dsname on fopen, there will be no DYNALLOC etc. and no SYSx ddnames, because there is already a ddname. I understand that those synthetic ddnames like SYS1 etc. are only needed, if you specify dsnames on fopen. Or, another case, if you do output to stdout by printf, for example, but SYSPRINT is already blocked (used, opened) by PL/1 (for example). Kind regards Bernd Am 30.04.2012 22:20, schrieb Charles Mills: Thanks! At least too many OPEN's is better than too many DYNALLOC's *and* too many OPEN's. There isn't a way to update (or get) the PDS directory user data Not a huge deal to write your own BPAM library, but I agree. When I first came to z/OS C/C++ about two years ago I was surprised that there were not more z/OS-specific library routines (or z/OS-specific enhancements to the inherited-from-UNIX library routines). Charles -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Kirk Wolf Sent: Monday, April 30, 2012 11:11 AM To: IBM-MAIN@bama.ua.edu Subject: Re: Does C/LE open of DD:ddname(member) use SVC 99 or FIND? Charles, I'm nearly certain that it doesn't do a SVC99 when you are using fopen with a DDNAME But it does seem to do a OPEN/BLDL/POINTSTOW/CLOSEfor each fopen() / fclose() using //DD:MYDD(MEM) IMO, there are a couple of important missing things: 1) There isn't a way to update (or get) the PDS directory user data when processing the member with fopen()/fclose(). 2) You would really like to be able to do this: fopen(//DD:MYDD(MEM1), ...) freopen(//DD:MYDD(MEM2), ) so that the freopen() caused a STOW (if opened update) and a BLDL/POINT, and avoided the cost of a complete OPEN/CLOSE path.I don't think that it does that. So, for my money, better BPAM support would be nice. Kirk Wolf Dovetailed Technologies http://dovetail.com On Mon, Apr 30, 2012 at 11:45 AM, Charles Millscharl...@mcn.org wrote: Does anyone *know* whether a C/C++ Language Environment fopen() of a filename of the form DD:ddname(member) use an OPEN of ddname followed by a BLDL or FIND for member (the way any reasonable programmer would) or does it do a whole new DYNALLOC for dsname(member)? (Seems like a dumb question, but FTP does it that way, so stranger things have happened.) My *interpretation* of the allocation messages - I don't see allocate and de-allocate messages for a SYSn that appears to be for member - leads me to believe that C/C++ LE does it right. But I could be reading it wrong. Does anyone *know*? Thanks, Charles -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
