The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.
CAIRO_STATUS_SUCCESS
     (integer)
    CAIRO_STATUS_NO_MEMORY
     (integer)
    CAIRO_STATUS_INVALID_RESTORE
     (integer)
    CAIRO_STATUS_INVALID_POP_GROUP
     (integer)
    CAIRO_STATUS_NO_CURRENT_POINT
     (integer)
    CAIRO_STATUS_INVALID_MATRIX
     (integer)
    CAIRO_STATUS_INVALID_STATUS
     (integer)
    CAIRO_STATUS_NULL_POINTER
     (integer)
    CAIRO_STATUS_INVALID_STRING
     (integer)
    CAIRO_STATUS_INVALID_PATH_DATA
     (integer)
    CAIRO_STATUS_READ_ERROR
     (integer)
    CAIRO_STATUS_WRITE_ERROR
     (integer)
    CAIRO_STATUS_SURFACE_FINISHED
     (integer)
    CAIRO_STATUS_SURFACE_TYPE_MISMATCH
     (integer)
    CAIRO_STATUS_PATTERN_TYPE_MISMATCH
     (integer)
    CAIRO_STATUS_INVALID_CONTENT
     (integer)
    CAIRO_STATUS_INVALID_FORMAT
     (integer)
    CAIRO_STATUS_INVALID_VISUAL
     (integer)
    CAIRO_STATUS_FILE_NOT_FOUND
     (integer)
    CAIRO_STATUS_INVALID_DASH
     (integer)
    CAIRO_STATUS_INVALID_DSC_COMMENT
     (integer)
    CAIRO_STATUS_INVALID_INDEX
     (integer)
    CAIRO_STATUS_CLIP_NOT_REPRESENTABLE
     (integer)
    CAIRO_STATUS_TEMP_FILE_ERROR
     (integer)
    CAIRO_STATUS_INVALID_STRIDE
     (integer)
    CAIRO_ANTIALIAS_DEFAULT
     (integer)
    CAIRO_ANTIALIAS_NONE
     (integer)
    CAIRO_ANTIALIAS_GRAY
     (integer)
    CAIRO_ANTIALIAS_SUBPIXEL
     (integer)
    CAIRO_SUBPIXEL_ORDER_DEFAULT
     (integer)
    CAIRO_SUBPIXEL_ORDER_RGB
     (integer)
    CAIRO_SUBPIXEL_ORDER_BGR
     (integer)
    CAIRO_SUBPIXEL_ORDER_VRGB
     (integer)
    CAIRO_SUBPIXEL_ORDER_VBGR
     (integer)
    CAIRO_FILL_RULE_WINDING
     (integer)
    CAIRO_FILL_RULE_EVEN_ODD
     (integer)
    CAIRO_LINE_CAP_BUTT
     (integer)
    CAIRO_LINE_CAP_ROUND
     (integer)
    CAIRO_LINE_CAP_SQUARE
     (integer)
    CAIRO_LINE_JOIN_MITER
     (integer)
    CAIRO_LINE_JOIN_ROUND
     (integer)
    CAIRO_LINE_JOIN_BEVEL
     (integer)
    CAIRO_OPERATOR_CLEAR
     (integer)
    CAIRO_OPERATOR_SOURCE
     (integer)
    CAIRO_OPERATOR_OVER
     (integer)
    CAIRO_OPERATOR_IN
     (integer)
    CAIRO_OPERATOR_OUT
     (integer)
    CAIRO_OPERATOR_ATOP
     (integer)
    CAIRO_OPERATOR_DEST
     (integer)
    CAIRO_OPERATOR_DEST_OVER
     (integer)
    CAIRO_OPERATOR_DEST_IN
     (integer)
    CAIRO_OPERATOR_DEST_OUT
     (integer)
    CAIRO_OPERATOR_DEST_ATOP
     (integer)
    CAIRO_OPERATOR_XOR
     (integer)
    CAIRO_OPERATOR_ADD
     (integer)
    CAIRO_OPERATOR_SATURATE
     (integer)
    CAIRO_PATTERN_TYPE_SOLID
     (integer)
    CAIRO_PATTERN_TYPE_SURFACE
     (integer)
    CAIRO_PATTERN_TYPE_LINEAR
     (integer)
    CAIRO_PATTERN_TYPE_RADIAL
     (integer)
    CAIRO_EXTEND_NONE
     (integer)
    CAIRO_EXTEND_REPEAT
     (integer)
    CAIRO_EXTEND_REFLECT
     (integer)
    CAIRO_EXTEND_PAD
     (integer)
    CAIRO_FILTER_FAST
     (integer)
    CAIRO_FILTER_GOOD
     (integer)
    CAIRO_FILTER_BEST
     (integer)
    CAIRO_FILTER_NEAREST
     (integer)
    CAIRO_FILTER_BILINEAR
     (integer)
    CAIRO_FILTER_GAUSSIAN
     (integer)
    CAIRO_HINT_STYLE_DEFAULT
     (integer)
    CAIRO_HINT_STYLE_NONE
     (integer)
    CAIRO_HINT_STYLE_SLIGHT
     (integer)
    CAIRO_HINT_STYLE_MEDIUM
     (integer)
    CAIRO_HINT_STYLE_FULL
     (integer)
    CAIRO_HINT_METRICS_DEFAULT
     (integer)
    CAIRO_HINT_METRICS_OFF
     (integer)
    CAIRO_HINT_METRICS_ON
     (integer)
    CAIRO_FONT_TYPE_TOY
     (integer)
    CAIRO_FONT_TYPE_FT
     (integer)
    CAIRO_FONT_TYPE_WIN32
     (integer)
    CAIRO_FONT_TYPE_QUARTZ
     (integer)
    CAIRO_FONT_SLANT_NORMAL
     (integer)
    CAIRO_FONT_SLANT_ITALIC
     (integer)
    CAIRO_FONT_SLANT_OBLIQUE
     (integer)
    CAIRO_FONT_WEIGHT_NORMAL
     (integer)
    CAIRO_FONT_WEIGHT_BOLD
     (integer)
    CAIRO_CONTENT_COLOR
     (integer)
    CAIRO_CONTENT_ALPHA
     (integer)
    CAIRO_CONTENT_COLOR_ALPHA
     (integer)
    CAIRO_SURFACE_TYPE_IMAGE
     (integer)
    CAIRO_SURFACE_TYPE_PDF
     (integer)
    CAIRO_SURFACE_TYPE_PS
     (integer)
    CAIRO_SURFACE_TYPE_XLIB
     (integer)
    CAIRO_SURFACE_TYPE_XCB
     (integer)
    CAIRO_SURFACE_TYPE_GLITZ
     (integer)
    CAIRO_SURFACE_TYPE_QUARTZ
     (integer)
    CAIRO_SURFACE_TYPE_WIN32
     (integer)
    CAIRO_SURFACE_TYPE_BEOS
     (integer)
    CAIRO_SURFACE_TYPE_DIRECTFB
     (integer)
    CAIRO_SURFACE_TYPE_SVG
     (integer)
    CAIRO_SURFACE_TYPE_OS2
     (integer)
    CAIRO_SURFACE_TYPE_WIN32_PRINTING
     (integer)
    CAIRO_SURFACE_TYPE_QUARTZ_IMAGE
     (integer)
    CAIRO_FORMAT_ARGB32
     (integer)
    CAIRO_FORMAT_RGB24
     (integer)
    CAIRO_FORMAT_A8
     (integer)
    CAIRO_FORMAT_A1
     (integer)
    CAIRO_PS_LEVEL_2
     (integer)
    CAIRO_PS_LEVEL_3
     (integer)
    CAIRO_SVG_VERSION_1_1
     (integer)
    CAIRO_SVG_VERSION_1_2
     (integer)