Earlier versions of this ABI included a description of vector programming interfaces and techniques for POWER®, along with an appendix enumerating the supported vector built-in functions. Most of this information is not ABI, and is removed from this version of the document. Instead, those interested are encouraged to now refer to the POWER Vector Intrinsics Programming Reference, available from the OpenPOWER Foundation in their Technical Resources Catalog ().

Support for vector variable input and output may be provided as an extension to the following POSIX library functions for the new vector conversion format strings: scanf fscanf sscanf wsscanf printf fprintf sprintf snprintf wsprintf vprintf vfprintf vsprintf vwsprintf (One sample implementation for such an extended specification is libvecprintf.) The size formatters are as follows: vl or lv consumes one argument and modifies an existing integer conversion, resulting in vector signed int, vector unsigned int, or vector bool for output conversions or vector signed int * or vector unsigned int * for input conversions. The data is then treated as a series of four 4-byte components, with the subsequent conversion format applied to each. vh or hv consumes one argument and modifies an existing short integer conversion, resulting in vector signed short or vector unsigned short for output conversions or vector signed short * or vector unsigned short * for input conversions. The data is treated as a series of eight 2-byte components, with the subsequent conversion format applied to each. v consumes one argument and modifies a 1-byte integer, 1-byte character, or 4-byte floating-point conversion. If the conversion is a floating-point conversion, the result is vector float for output conversion or vector float * for input conversion. The data is treated as a series of four 4-byte floating-point components with the subsequent conversion format applied to each. If the conversion is an integer or character conversion, the result is either vector signed char, vector unsigned char, or vector bool char for output conversion, or vector signed char * or vector unsigned char * for input conversions. The data is treated as a series of sixteen 1-byte components, with the subsequent conversion format applied to each. vv consumes one argument and modifies an 8-byte floating-point conversion. If the conversion is a floating-point conversion, the result is vector double for output conversion or vector double * for input conversion. The data is treated as a series of two 8-byte floating-point components with the subsequent conversion format applied to each. Integer and byte conversions are not defined for the vv modifier. As new vector types are defined, new format codes should be defined to support scanf and printf of those types. Any conversion format that can be applied to the singular form of a vector-data type can be used with a vector form. The %d, %x, %X, %u, %i, and %o integer conversions can be applied with the %lv, %vl, %hv, %vh, and %v vector-length qualifiers. The %c character conversion can be applied with the %v vector length qualifier. The %a, %A, %e, %E, %f, %F, %g, and %G float conversions can be applied with the %v vector length qualifier. For input conversions, an optional separator character can be specified excluding white space preceding the separator. If no separator is specified, the default separator is a space including white space characters preceding the separator, unless the conversion is c. Then, the default conversion is null. For output conversions, an optional separator character can be specified immediately preceding the vector size conversion. If no separator is specified, the default separator is a space unless the conversion is c. Then, the default separator is null.