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Release 7.50 Changes to the SAS/C Library Reference, Volume 1

In Chapter 2, "Function Categories," update the information for the different types of functions with the following text.

Math Functions

Update the math functions, for example, exp, atan, with the following enhancements.

All of the math functions support calls from functions compiled with the bfp option.
All of the math functions support float and long double callers if the name is suffixed with the letter f or l.
All of the math functions other than fmod are declared as macros in tgmath.h, and can be used in a type-generic fashion if that header file is included.
Math functions which are documented as calling _matherr in case of errors will call _matherb instead if invoked from a caller compiled with the bfp option.
The values returned for domain and range errors may differ for bfp callers from the documented values. In general, a NaN will be returned for domain errors. Overflow will produce an infinity or the largest possible finite number, depending on the rounding mode. Underflow will produce a denormalized result or a zero depending on the magnitude of the correct answer and the rounding mode. A singularity will produce an infinite result.
Except in a few degenerate cases, for example, pow(1.0, NaN), any function called with an argument that is a NaN will return a NaN.

Other changes or enhancements to existing functions worth noting are:

The sqrt function is now built-in if binary floating point is used, or if the compiler option archlevel(c) is used.
The function name lgamma is provided as a synonym for gamma. The lgamma name is preferred because it more accurately describes the function.
The function prototypes for fmax, fmin, hypot, erf and erfc were previously defined only in lcmath.h. Because these functions are defined by the C99 standard, their prototypes are now also in math.h.

Add the following functions to the list of string functions.

nan convert a string to an IEEE double NaN

nanf convert a string to an IEEE float NaN

nanl convert a string to an IEEE long double NaN

Timing Functions

The following paragraph:

The resolution and accuracy of time values vary from implementation to implementation. Timing functions under traditional UNIX C compilers return a value of type long. The library implements time_t as a double to allow more accurate time measurement. Keep this difference in mind for programs ported among several environments.

Should read:

The resolution and accuracy of time values vary from implementation to implementation. Timing functions under traditional UNIX C compilers return a value of type long. The library implements time_t and clock_t as hex format doubles to allow more accurate time measurement. This is permitted by the ANSI/ISO standards, but is unusual, as most systems define these types as integral types. This can lead to problems in programs ported from other environments. Also note that programs which use the bfp option may receive diagnostics if they attempt to evaluate expressions with both a time_t or clock_t operand and one or more double operands. Casting the time_t or clock_t value to a _ _binfmt double is recommended to solve such problems.

Updates to the SAS/C Functions

The following sections contain updates to the SAS/C functions in Chapter 6, "Function Descriptions."

llmax

Replace the SYNOPSIS and EXAMPLE sections with the following new sections:

SYNOPSIS

#include <lclib.h>

long long int llmax(long long int s, long long int r);

EXAMPLE

#include <lclib.h>
#include <stdio.h>

main()
{
long long int num1, num2; /* numbers to be compared */
long long int result; /* holds the larger of num1 and num2 */

puts("Enter num1 & num2 : ");
scanf("%lld %lld", &num1, &num2);
result = llmax(num1, num2);
printf("The larger number is %lld\n", result);
}

llmin

Replace the SYNOPSIS and EXAMPLE sections with the following new sections:

SYNOPSIS

#include <lclib.h>

long long int llmin(long long int s, long long int r);

EXAMPLE

#include <lclib.h>
#include <stdio.h>

main()
{
long long int num1, num2; /* numbers to be compared */
long long int result; /* holds the smaller of num1 and num2 */

puts("Enter num1 & num2 : ");
scanf("%lld %lld", &num1, &num2);
result = llmin(num1, num2);
printf("The smaller number is %lld\n", result);
}

storck

In the "DESCRIPTION" section of the storck function entry, make the following changes:

Change the last list-item term, STROCK_STACK_REPT, to STORCK_STACK_REPT.
Change the OS/390 Batch default value, DDN:DBGSTG, to DDN:STGRPT.

Updates to Multi-Volume Seeks Support

In Chapter 3, "I/O Functions," add the following information for multi-volume seeks support.

In the section titled, "Library access methods," in the information on the rel access method Under OS/390, add the following text after the list:
Under OS/390, datasets are allowed to extend to multiple volumes.

In the section titled, "File positioning with standard I/O (fseek and ftell)," add the following entry to the table labeled, "OS/390 Files with Restricted Positioning:"

OS/390 Files with Restricted Positioning
File Type Restrictions

multivolume disk or tape file For non-rel datasets: only rewind supported if not opened for append; only seek to the end of file supported if opened for append

***OS/390 Files with Restricted Positioning***
File Type	Restrictions
multivolume disk or tape file	For non-rel datasets: only rewind supported if not opened for append; only seek to the end of file supported if opened for append

New WTP Function

In Release 7.50, the WTP macro has been changed to a function. Because of this change, several modifications need to be made to the SAS/C Library Reference, Volume 1.

In Chapter 1, "Introduction to the SAS/C Library," in the section titled "Implementation of Functions," delete WTP from the list of SAS/C functions implemented as macros.
In Chapter 6, "Function Descriptions," in the wto function description, delete the reference to the WTP macro, delete the sample showing the WTP macro, and add WTP to the list of related functions.
In Chapter 6, "Function Descriptions," add the function description for WTP at WTP to the list of functions.

Updates to SAS/C I/O Questions and Answers

In Chapter 3, "I/O Functions," in the section titled, "SAS/C I/O Questions and Answers," replace the section titled, "Sharing an Output PDS" with the following text.

Q. When I open a PDS member for output, the fopen call fails if another user has the PDS allocated, even if it is allocated as SHR. How can I write to the PDS if it shared with another user?

A. If more than one user writes to the same PDS at the same time, the results are unpredictable. Generally, both members will be damaged. For this reason, when a PDS member, or any other OS/390 data set, is opened for output, the library allocates the data set to OLD to make sure that no one else writes to it at the same time. In some cases, this may be overprotective, but it prevents file damage from unintended simultaneous access. In cases where the PDS will only be updated via SAS/C or ISPF, or other applications that conform to the ISPF enqueing mechanism, you can specifiy share=ispf as an amparm when you open the member to force the library to open the dataset as shared.
Note: With a PDSE, it is possible to simultaneously write to distinct members. Even with a PDSE, the effects are unpredictable if the same member is opened by more than one user for output at the same time. [cautionend]

Updates to Signal-Handling Functions

Update to USS Supported Signals

In Chapter 5, "Signal-Handling Functions," in the section titled "Supported Signals," add the following entry to the list of signals managed exclusively by USS:

SIGDUMP request for SYSMDUMP

Updates to Information on Signals

In Chapter 5, "Signal-Handling Functions," add the following information for the new SIGBFPE and SIGOPER signals and for updates to other signals.

In the section titled, "Synchronous Signals," add SIGBFPE to the list of sychronous signals.
In the section titled, "Asynchronous Signals," add SIGOPER to the list of signals.
In the section titled, "Supported Signals," add SIGBFPE and SIGOPER to the list of signals managed exclusively by SAS/C.

Add the following entries to the table labeled, "Summary of Information from siginfo."

Summary of Information from siginfo
Signal Information Returned by siginfo for Signals Raised Naturally

SIGBFPE
pointer to structure of type FPE_t

SIGOPER
pointer to structure of type OPER_t

***Summary of Information from siginfo***
Signal	Information Returned by `siginfo` for Signals Raised Naturally
`SIGBFPE`	pointer to structure of type `FPE_t`
`SIGOPER`	pointer to structure of type `OPER_t`

In the section titled, "Default Signal Handling," add the following entries to the table labeled, "Summary of Default Actions."

Summary of Default Actions
Signal SAS/C Library Default Action(SIG_DFL Handler) USS Default Action(SIG_DFL Handler)

SIGBFPE
ABEND with 0C7 not supported

SIGOPER
ABEND with user code 1225 ends the process

***Summary of Default Actions***
Signal	SAS/C Library Default Action(`SIG_DFL` Handler)	USS Default Action(`SIG_DFL` Handler)
`SIGBFPE`	ABEND with 0C7	not supported
`SIGOPER`	ABEND with user code 1225	ends the process

In the section titled, "Ignoring Signals," add the following entry to the table labeled, "Summary of Ignoring Signals."

Summary of Ignoring Signals
Signal SAS/C Library Ignored Signals(SIG_IGN Handler) USS Ignored Signals(SIG_IGN Handler)

SIGBFPE
program continues; result of computation undefined not supported

In the section titled, "Signal Descriptions," add the following updates:
- Change the first sentence of the SIGFPDIV description to read:
  The SIGFPDIV signal is raised when the second operand of a hexadecimal format floating point division is zero, and default handling is in effect for SIGFPE.
- Change the first sentence of the SIGFPOFL description to read:
  The SIGFPOFL signal is raised when the magnitude of the result of a hexadecimal format floating-point computation exceeds the maximum supported by the hardware and default handling is in effect for SIGFPE .
- Change the first sentence of the SIGFPUFL description to read:
  The SIGFPUFL signal is raised when the magnitude of the result of a hexadecimal format floating-point computation exceeds the maximum supported by the hardware and default handling is in effect for SIGFPE .

***Summary of Ignoring Signals***
Signal	SAS/C Library Ignored Signals(`SIG_IGN` Handler)	USS Ignored Signals(`SIG_IGN` Handler)
`SIGBFPE`	program continues; result of computation undefined	not supported

New SIGBFPE and SIGOPER Signals

In the section titled, "Signal Descriptions," add the following entries for SIGBFPE and SIGOPERto the list of descriptions.

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`nan`	convert a string to an IEEE double NaN
`nanf`	convert a string to an IEEE float NaN
`nanl`	convert a string to an IEEE long double NaN