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HP OpenVMS SystemsC Programming Language |
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HP C
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The __ALLOCA function allocates n bytes from the stack.
This function has the following format:
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void *__ALLOCA (unsigned int n); |
n
The number of bytes to be allocated.
A pointer to the allocated memory is returned.
The __AND_ATOMIC_LONG function performs a bit-wise or arithmetic AND of the specified expression with the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence.
This function has the following format:
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int __AND_ATOMIC_LONG (void *address, int expression, ...); |
address
The longword-aligned address of the data segment.expression
An integer expression....
An optional retry count of type int . If specified, the retry count indicates the number of times the operation is attempted (which will be at least once, even if the count argument is 0). If the operation cannot be performed successfully in the specified number of retries, a value of 0 is returned. If the operation is successful, a value of 1 is returned.
If the optional retry count is omitted, this function loops back for a retry unconditionally on failure. In this case, the function can never return a failure value. It either returns a value of 1 upon successful completion, or hangs in an endless failure loop. |
The __AND_ATOMIC_QUAD function performs a bit-wise or arithmetic AND of the specified expression with the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence.
This function has the following format:
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int __AND_ATOMIC_QUAD (void *address, int expression, ...); |
address
The address of the aligned quadword.expression
An integer expression....
An optional retry count of type int . If specified, the retry count indicates the number of times the operation is attempted (which will be at least once, even if the count argument is 0). If the operation cannot be performed successfully in the specified number of retries, a value of 0 is returned. If the operation is successful, a value of 1 is returned.
If the optional retry count is omitted, this function loops back for a retry unconditionally on failure. In this case, the function can never return a failure value. It either returns a value of 1 upon successful completion, or hangs in an endless failure loop. |
The __ATOMIC_ADD_LONG function adds the specified expression to the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the longword before the addition was performed.
This function has the following formats:
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int __ATOMIC_ADD_LONG (volatile void *address, int expression); int __ATOMIC_ADD_LONG_RETRY (volatile void *address, int expression, int retry, int *status); |
address
The longword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the longword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_ADD_QUAD function adds the specified expression to the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the quadword before the addition was performed.
This function has the following formats:
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__int64 __ATOMIC_ADD_QUAD (volatile void *address, __int64 expression); __int64 __ATOMIC_ADD_QUAD_RETRY (volatile void *address, __int64 expression, int retry, int *status); |
address
The quadword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_AND_LONG function performs a bit-wise or arithmetic AND of the specified expression with the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the longword before the operation was performed.
This function has the following formats:
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int __ATOMIC_AND_LONG (volatile void *address, int expression); int __ATOMIC_AND_LONG_RETRY (volatile void *address, int expression, int retry, int *status); |
address
The longword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the longword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_AND_QUAD function performs a bit-wise or arithmetic AND of the specified expression with the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the quadword before the operation was performed.
This function has the following formats:
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__int64 __ATOMIC_AND_QUAD (volatile void *address, __int64 expression); __int64 __ATOMIC_AND_QUAD_RETRY (volatile void *address, __int64 expression, int retry, int *status); |
address
The quadword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_OR_LONG function performs a bit-wise or arithmetic OR of the specified expression with the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the longword before the operation was performed.
This function has the following formats:
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int __ATOMIC_OR_LONG (volatile void *address, int expression); int __ATOMIC_OR_LONG_RETRY (volatile void *address, int expression, int retry, int *status); |
address
The longword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the longword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_OR_QUAD function performs a bit-wise or arithmetic OR of the specified expression with the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the quadword before the operation was performed.
This function has the following formats:
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__int64 __ATOMIC_OR_QUAD (volatile void *address, __int64 expression); __int64 __ATOMIC_OR_QUAD_RETRY (volatile void *address, __int64 expression, int retry, int *status); |
address
The quadword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_INCREMENT_LONG function increments by 1 the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the longword before the operation was performed.
This function has the following formats:
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int __ATOMIC_INCREMENT_LONG (volatile void *address); int __ATOMIC_INCREMENT_LONG_RETRY (volatile void *address, int retry, int *status); |
address
The longword-aligned address of the data segment.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The __ATOMIC_INCREMENT_QUAD function increments by 1 the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the quadword before the operation was performed.
This function has the following formats:
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__int64 __ATOMIC_INCREMENT_QUAD (volatile void *address); __int64 __ATOMIC_INCREMENT_QUAD (volatile void *address, int retry, int *status); |
address
The quadword-aligned address of the data segment.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The __ATOMIC_DECREMENT_LONG function decrements by 1 the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the longword before the operation was performed.
This function has the following formats:
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int __ATOMIC_DECREMENT_LONG (volatile void *address); int __ATOMIC_DECREMENT_LONG (volatile void *address, int retry, int *status); |
address
The longword-aligned address of the data segment.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The __ATOMIC_DECREMENT_QUAD function decrements by 1 the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the quadword before the operation was performed.
This function has the following formats:
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__int64 __ATOMIC_DECREMENT_QUAD (volatile void *address); __int64 __ATOMIC_DECREMENT_QUAD (volatile void *address, int retry, int *status); |
address
The quadword-aligned address of the data segment.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The __ATOMIC_EXCH_LONG function stores the value of the specified expression into the aligned longword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the longword before the operation was performed.
This function has the following formats:
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int __ATOMIC_EXCH_LONG (volatile void *address, int expression); int __ATOMIC_EXCH_LONG_RETRY (volatile void *address, int expression, int retry, int *status); |
address
The longword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the longword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __ATOMIC_EXCH_QUAD function stores the value of the specified expression into the aligned quadword pointed to by the address parameter within a load-locked/store-conditional code sequence and returns the value of the quadword before the operation was performed.
This function has the following formats:
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__int64 __ATOMIC_EXCH_QUAD (volatile void *address, __int64 expression); __int64 __ATOMIC_EXCH_QUAD_RETRY (volatile void *address, __int64 expression, int retry, int *status); |
address
The quadword-aligned address of the data segment.expression
An integer expression.retry
A retry count of type int that indicates the number of times the operation is attempted (which is at least once, even if the retry argument is 0). If the operation cannot be performed successfully in the specified number of retries, the function returns without updating the quadword.status
A pointer to an integer that is set to 0 if the operation did not succeed within the specified number of retries, and set to 1 if the operation succeeded.
The non-RETRY form of this function loops back for a retry unconditionally on failure. This means this function can hang in an endless failure loop. |
The __CMP_STORE_LONG function has the following format:
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int __CMP_STORE_LONG (volatile void *source, int old_value, int new_value, volatile void *dest); |
This function performs a conditional atomic compare and update operation involving one or two longwords in the same lock region. The value pointed to by source is compared with the longword old_value. If they are equal, the longword new_value is conditionally stored into the value pointed to by dest.
The store will not complete if the compare yields unequal values or if there is an intervening store to the lock region involved. To be in the same lock region, source and dest must point to aligned longwords in the same naturally aligned 16-byte region.
The function returns 0 if the store does not complete, and returns 1 if the store does complete.
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