Module stdinc

Available on crate feature dep_sdl3 only.

SDL provides its own implementation of some of the most important C runtime functions.

Using these functions allows an app to have access to common C functionality without depending on a specific C runtime (or a C runtime at all). More importantly, the SDL implementations work identically across platforms, so apps can avoid surprises like snprintf() behaving differently between Windows and Linux builds, or itoa() only existing on some platforms.

For many of the most common functions, like SDL_memcpy, SDL might just call through to the usual C runtime behind the scenes, if it makes sense to do so (if it’s faster and always available/reliable on a given platform), reducing library size and offering the most optimized option.

SDL also offers other C-runtime-adjacent functionality in this header that either isn’t, strictly speaking, part of any C runtime standards, like SDL_crc32() and [SDL_reinterpret_cast], etc. It also offers a few better options, like SDL_strlcpy(), which functions as a safer form of strcpy().

Structs

SDL_Environment

A thread-safe set of environment variables

SDL_iconv_data_t

Constants

SDL_FLT_EPSILON

SDL_ICONV_E2BIG

Output buffer was too small.

SDL_ICONV_EILSEQ

Invalid input sequence was encountered.

SDL_ICONV_EINVAL

Incomplete input sequence was encountered.

SDL_ICONV_ERROR

Generic error. Check [SDL_GetError()]?

SDL_INVALID_UNICODE_CODEPOINT

The Unicode REPLACEMENT CHARACTER codepoint.

SDL_MAX_SINT8

SDL_MAX_SINT16

SDL_MAX_SINT32

SDL_MAX_SINT64

SDL_MAX_TIME

SDL_MAX_UINT8

SDL_MAX_UINT16

SDL_MAX_UINT32

SDL_MAX_UINT64

SDL_MIN_SINT8

SDL_MIN_SINT16

SDL_MIN_SINT32

SDL_MIN_SINT64

SDL_MIN_TIME

SDL_MIN_UINT8

SDL_MIN_UINT16

SDL_MIN_UINT32

SDL_MIN_UINT64

SDL_PI_D

The value of Pi, as a double-precision floating point literal.

SDL_PI_F

The value of Pi, as a single-precision floating point literal.

SDL_PRILLX

SDL_PRILL_PREFIX

SDL_PRILLd

SDL_PRILLu

SDL_PRILLx

SDL_PRIX32

SDL_PRIX64

SDL_PRIs32

SDL_PRIs64

SDL_PRIu32

SDL_PRIu64

SDL_PRIx32

SDL_PRIx64

SDL_SIZE_MAX

Functions

SDL_CreateEnvironment^⚠

Create a set of environment variables

SDL_DestroyEnvironment^⚠

Destroy a set of environment variables.

SDL_FOURCC

Define a four character code as a Uint32.

SDL_GetEnvironment^⚠

Get the process environment.

SDL_GetEnvironmentVariable^⚠

Get the value of a variable in the environment.

SDL_GetEnvironmentVariables^⚠

Get all variables in the environment.

SDL_GetMemoryFunctions^⚠

Get the current set of SDL memory functions.

SDL_GetNumAllocations^⚠

Get the number of outstanding (unfreed) allocations.

SDL_GetOriginalMemoryFunctions^⚠

Get the original set of SDL memory functions.

SDL_INIT_INTERFACE^⚠

A macro to initialize an SDL interface.

SDL_SetEnvironmentVariable^⚠

Set the value of a variable in the environment.

SDL_SetMemoryFunctions^⚠

Replace SDL’s memory allocation functions with a custom set.

SDL_StepBackUTF8^⚠

Decode a UTF-8 string in reverse, one Unicode codepoint at a time.

SDL_StepUTF8^⚠

Decode a UTF-8 string, one Unicode codepoint at a time.

SDL_UCS4ToUTF8^⚠

Convert a single Unicode codepoint to UTF-8.

SDL_UnsetEnvironmentVariable^⚠

Clear a variable from the environment.

SDL_abs^⚠

Compute the absolute value of x.

SDL_acos^⚠

Compute the arc cosine of x.

SDL_acosf^⚠

Compute the arc cosine of x.

SDL_aligned_alloc^⚠

Allocate memory aligned to a specific alignment.

SDL_aligned_free^⚠

Free memory allocated by SDL_aligned_alloc().

SDL_asin^⚠

Compute the arc sine of x.

SDL_asinf^⚠

Compute the arc sine of x.

SDL_asprintf^⚠

This works exactly like asprintf() but doesn’t require access to a C runtime.

SDL_atan^⚠

Compute the arc tangent of x.

SDL_atan2^⚠

Compute the arc tangent of y / x, using the signs of x and y to adjust the result’s quadrant.

SDL_atan2f^⚠

Compute the arc tangent of y / x, using the signs of x and y to adjust the result’s quadrant.

SDL_atanf^⚠

Compute the arc tangent of x.

SDL_atof^⚠

Parse a double from a string.

SDL_atoi^⚠

Parse an int from a string.

SDL_bsearch^⚠

Perform a binary search on a previously sorted array.

SDL_bsearch_r^⚠

Perform a binary search on a previously sorted array, passing a userdata pointer to the compare function.

SDL_calloc^⚠

Allocate a zero-initialized array.

SDL_ceil^⚠

Compute the ceiling of x.

SDL_ceilf^⚠

Compute the ceiling of x.

SDL_clamp

SDL_copyp^⚠

A macro to copy memory between objects, with basic type checking.

SDL_copysign^⚠

Copy the sign of one floating-point value to another.

SDL_copysignf^⚠

Copy the sign of one floating-point value to another.

SDL_cos^⚠

Compute the cosine of x.

SDL_cosf^⚠

Compute the cosine of x.

SDL_crc16^⚠

Calculate a CRC-16 value.

SDL_crc32^⚠

Calculate a CRC-32 value.

SDL_exp^⚠

Compute the exponential of x.

SDL_expf^⚠

Compute the exponential of x.

SDL_fabs^⚠

Compute the absolute value of x

SDL_fabsf^⚠

Compute the absolute value of x

SDL_floor^⚠

Compute the floor of x.

SDL_floorf^⚠

Compute the floor of x.

SDL_fmod^⚠

Return the floating-point remainder of x / y

SDL_fmodf^⚠

Return the floating-point remainder of x / y

SDL_free^⚠

Free allocated memory.

SDL_getenv^⚠

Get the value of a variable in the environment.

SDL_getenv_unsafe^⚠

Get the value of a variable in the environment.

SDL_iconv^⚠

This function converts text between encodings, reading from and writing to a buffer.

SDL_iconv_close^⚠

This function frees a context used for character set conversion.

SDL_iconv_open^⚠

This function allocates a context for the specified character set conversion.

SDL_iconv_string^⚠

Helper function to convert a string’s encoding in one call.

SDL_iconv_utf8_locale^⚠

Convert a UTF-8 string to the current locale’s character encoding.

SDL_iconv_utf8_ucs2^⚠

Convert a UTF-8 string to UCS-2.

SDL_iconv_utf8_ucs4^⚠

Convert a UTF-8 string to UCS-4.

SDL_iconv_wchar_utf8^⚠

Convert a wchar_t string to UTF-8.

SDL_isalnum^⚠

Query if a character is alphabetic (a letter) or a number.

SDL_isalpha^⚠

Query if a character is alphabetic (a letter).

SDL_isblank^⚠

Report if a character is blank (a space or tab).

SDL_iscntrl^⚠

Report if a character is a control character.

SDL_isdigit^⚠

Report if a character is a numeric digit.

SDL_isgraph^⚠

Report if a character is any “printable” except space.

SDL_isinf^⚠

Return whether the value is infinity.

SDL_isinff^⚠

Return whether the value is infinity.

SDL_islower^⚠

Report if a character is lower case.

SDL_isnan^⚠

Return whether the value is NaN.

SDL_isnanf^⚠

Return whether the value is NaN.

SDL_isprint^⚠

Report if a character is “printable”.

SDL_ispunct^⚠

Report if a character is a punctuation mark.

SDL_isspace^⚠

Report if a character is whitespace.

SDL_isupper^⚠

Report if a character is upper case.

SDL_isxdigit^⚠

Report if a character is a hexadecimal digit.

SDL_itoa^⚠

Convert an integer into a string.

SDL_lltoa^⚠

Convert a long long integer into a string.

SDL_log^⚠

Compute the natural logarithm of x.

SDL_log10^⚠

Compute the base-10 logarithm of x.

SDL_log10f^⚠

Compute the base-10 logarithm of x.

SDL_logf^⚠

Compute the natural logarithm of x.

SDL_lround^⚠

Round x to the nearest integer representable as a long

SDL_lroundf^⚠

Round x to the nearest integer representable as a long

SDL_ltoa^⚠

Convert a long integer into a string.

SDL_malloc^⚠

Allocate uninitialized memory.

SDL_max

SDL_memcmp^⚠

Compare two buffers of memory.

SDL_memcpy^⚠

Copy non-overlapping memory.

SDL_memmove^⚠

Copy memory ranges that might overlap.

SDL_memset^⚠

Initialize all bytes of buffer of memory to a specific value.

SDL_memset4^⚠

Initialize all 32-bit words of buffer of memory to a specific value.

SDL_min

SDL_modf^⚠

Split x into integer and fractional parts

SDL_modff^⚠

Split x into integer and fractional parts

SDL_murmur3_32^⚠

Calculate a 32-bit MurmurHash3 value for a block of data.

SDL_pow^⚠

Raise x to the power y

SDL_powf^⚠

Raise x to the power y

SDL_qsort^⚠

Sort an array.

SDL_qsort_r^⚠

Sort an array, passing a userdata pointer to the compare function.

SDL_rand^⚠

Generate a pseudo-random number less than n for positive n

SDL_rand_bits^⚠

Generate 32 pseudo-random bits.

SDL_rand_bits_r^⚠

Generate 32 pseudo-random bits.

SDL_rand_r^⚠

Generate a pseudo-random number less than n for positive n

SDL_randf^⚠

Generate a uniform pseudo-random floating point number less than 1.0

SDL_randf_r^⚠

Generate a uniform pseudo-random floating point number less than 1.0

SDL_realloc^⚠

Change the size of allocated memory.

SDL_round^⚠

Round x to the nearest integer.

SDL_roundf^⚠

Round x to the nearest integer.

SDL_scalbn^⚠

Scale x by an integer power of two.

SDL_scalbnf^⚠

Scale x by an integer power of two.

SDL_setenv_unsafe^⚠

Set the value of a variable in the environment.

SDL_sin^⚠

Compute the sine of x.

SDL_sinf^⚠

Compute the sine of x.

SDL_size_add_check_overflow^⚠

Add two integers, checking for overflow.

SDL_size_mul_check_overflow^⚠

Multiply two integers, checking for overflow.

SDL_snprintf^⚠

This works exactly like snprintf() but doesn’t require access to a C runtime.

SDL_sqrt^⚠

Compute the square root of x.

SDL_sqrtf^⚠

Compute the square root of x.

SDL_srand^⚠

Seeds the pseudo-random number generator.

SDL_sscanf^⚠

This works exactly like sscanf() but doesn’t require access to a C runtime.

SDL_strcasecmp^⚠

Compare two null-terminated UTF-8 strings, case-insensitively.

SDL_strcasestr^⚠

Search a UTF-8 string for the first instance of a specific substring, case-insensitively.

SDL_strchr^⚠

Search a string for the first instance of a specific byte.

SDL_strcmp^⚠

Compare two null-terminated UTF-8 strings.

SDL_strdup^⚠

Allocate a copy of a string.

SDL_strlcat^⚠

Concatenate strings.

SDL_strlcpy^⚠

Copy a string.

SDL_strlen^⚠

This works exactly like strlen() but doesn’t require access to a C runtime.

SDL_strlwr^⚠

Convert a string to lowercase.

SDL_strncasecmp^⚠

Compare two UTF-8 strings, case-insensitively, up to a number of bytes.

SDL_strncmp^⚠

Compare two UTF-8 strings up to a number of bytes.

SDL_strndup^⚠

Allocate a copy of a string, up to n characters.

SDL_strnlen^⚠

This works exactly like strnlen() but doesn’t require access to a C runtime.

SDL_strnstr^⚠

Search a string, up to n bytes, for the first instance of a specific substring.

SDL_strpbrk^⚠

Searches a string for the first occurence of any character contained in a breakset, and returns a pointer from the string to that character.

SDL_strrchr^⚠

Search a string for the last instance of a specific byte.

SDL_strrev^⚠

Reverse a string’s contents.

SDL_strstr^⚠

Search a string for the first instance of a specific substring.

SDL_strtod^⚠

Parse a double from a string.

SDL_strtok_r^⚠

This works exactly like strtok_r() but doesn’t require access to a C runtime.

SDL_strtol^⚠

Parse a long from a string.

SDL_strtoll^⚠

Parse a long long from a string.

SDL_strtoul^⚠

Parse an unsigned long from a string.

SDL_strtoull^⚠

Parse an unsigned long long from a string.

SDL_strupr^⚠

Convert a string to uppercase.

SDL_swprintf^⚠

This works exactly like swprintf() but doesn’t require access to a C runtime.

SDL_tan^⚠

Compute the tangent of x.

SDL_tanf^⚠

Compute the tangent of x.

SDL_tolower^⚠

Convert low-ASCII English letters to lowercase.

SDL_toupper^⚠

Convert low-ASCII English letters to uppercase.

SDL_trunc^⚠

Truncate x to an integer.

SDL_truncf^⚠

Truncate x to an integer.

SDL_uitoa^⚠

Convert an unsigned integer into a string.

SDL_ulltoa^⚠

Convert an unsigned long long integer into a string.

SDL_ultoa^⚠

Convert an unsigned long integer into a string.

SDL_unsetenv_unsafe^⚠

Clear a variable from the environment.

SDL_utf8strlcpy^⚠

Copy an UTF-8 string.

SDL_utf8strlen^⚠

Count the number of codepoints in a UTF-8 string.

SDL_utf8strnlen^⚠

Count the number of codepoints in a UTF-8 string, up to n bytes.

SDL_vasprintf^⚠

This works exactly like vasprintf() but doesn’t require access to a C runtime.

SDL_vsnprintf^⚠

This works exactly like vsnprintf() but doesn’t require access to a C runtime.

SDL_vsscanf^⚠

This works exactly like vsscanf() but doesn’t require access to a C runtime.

SDL_vswprintf^⚠

This works exactly like vswprintf() but doesn’t require access to a C runtime.

SDL_wcscasecmp^⚠

Compare two null-terminated wide strings, case-insensitively.

SDL_wcscmp^⚠

Compare two null-terminated wide strings.

SDL_wcsdup^⚠

Allocate a copy of a wide string.

SDL_wcslcat^⚠

Concatenate wide strings.

SDL_wcslcpy^⚠

Copy a wide string.

SDL_wcslen^⚠

This works exactly like wcslen() but doesn’t require access to a C runtime.

SDL_wcsncasecmp^⚠

Compare two wide strings, case-insensitively, up to a number of wchar_t.

SDL_wcsncmp^⚠

Compare two wide strings up to a number of wchar_t values.

SDL_wcsnlen^⚠

This works exactly like wcsnlen() but doesn’t require access to a C runtime.

SDL_wcsnstr^⚠

Search a wide string, up to n wide chars, for the first instance of a specific substring.

SDL_wcsstr^⚠

Search a wide string for the first instance of a specific substring.

SDL_wcstol^⚠

Parse a long from a wide string.

SDL_zerop^⚠

Clear an object’s memory to zero, using a pointer.

Type Aliases

SDL_CompareCallback

A callback used with SDL sorting and binary search functions.

SDL_CompareCallback_r

A callback used with SDL sorting and binary search functions.

SDL_FunctionPointer

SDL_Time

SDL times are signed, 64-bit integers representing nanoseconds since the Unix epoch (Jan 1, 1970).

SDL_calloc_func

A callback used to implement SDL_calloc().

SDL_free_func

A callback used to implement SDL_free().

SDL_iconv_t

An opaque handle representing string encoding conversion state.

SDL_malloc_func

A callback used to implement SDL_malloc().

SDL_realloc_func

A callback used to implement SDL_realloc().

Sint8

A signed 8-bit integer type.

Sint16

A signed 16-bit integer type.

Sint32

A signed 32-bit integer type.

Sint64

A signed 64-bit integer type.

Uint8

An unsigned 8-bit integer type.

Uint16

An unsigned 16-bit integer type.

Uint32

An unsigned 32-bit integer type.

Uint64

An unsigned 64-bit integer type.