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Cx51 User's Guide

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Cx51 User's Guide

Cx51 Introduction Compiling Programs Language Extensions Preprocessor Advanced Programming 8051 Derivatives Error Messages Library Reference Library Files Source Code Standard Types jmp_buf size_t va_list wchar_t Macros CBYTE CWORD DBYTE DWORD FARRAY FCARRAY FCVAR FVAR PBYTE PWORD XBYTE XWORD Routines By Category Buffer Manipulation Routines Character Routines Data Conversion Routines Intrinsic Routines Math Routines Memory Allocation Routines Stream I/O Routines String Routines Variable Length Argument Routines Miscellaneous Routines Include Files SFR Definitions 80c517.h absacc.h assert.h ctype.h float.h intrins.h limits.h math.h rtx51tny.h setjmp.h stdarg.h stddef.h stdio.h stdlib.h string.h Reference _chkfloat_ _crol_ _cror_ _getkey _irol_ _iror_ _lrol_ _lror_ _nop_ _pop_ _push_ _testbit_ _tolower _toupper abs acos acos517 asin asin517 assert atan atan2 atan517 atof atof517 atoi atol cabs calloc ceil cos cos517 cosh exp exp517 fabs floor fmod free getchar gets init_mempool isalnum isalpha iscntrl isdigit isgraph islower isprint ispunct isspace isupper isxdigit labs log log10 log10517 log517 longjmp malloc memccpy memchr memcmp memcpy memmove memset modf offsetof pow printf printf517 putchar puts rand realloc scanf scanf517 setjmp sin sin517 sinh sprintf sprintf517 sqrt sqrt517 srand sscanf sscanf517 strcat strchr strcmp strcpy strcspn strlen strncat strncmp strncpy strpbrk strpos strrchr strrpbrk strrpos strspn strstr strtod strtod517 strtok strtol strtoul switchbank tan tan517 tanh toascii toint tolower toupper ungetchar va_arg va_end va_start vprintf vsprintf Appendix

String Routines

RoutineAttributesDescription
strcat Concatenates two strings.
strchrreentrantReturns a pointer to the first occurrence of a specified character in a string.
strcmpreentrantCompares two strings.
strcpyreentrantCopies one string to another.
strcspn Returns the index of the first character in a string that matches any character in a second string.
strlenreentrantReturns the length of a string.
strncat Concatenates up to a specified number of characters from one string to another.
strncmp Compares two strings up to a specified number of characters.
strncpy Copies up to a specified number of characters from one string to another.
strpbrk Returns a pointer to the first character in a string that matches any character in a second string.
strposreentrantReturns the index of the first occurrence of a specified character in a string.
strrchrreentrantReturns a pointer to the last occurrence of a specified character in a string.
strrpbrk Returns a pointer to the last character in a string that matches any character in a second string.
strrposreentrantReturns the index of the last occurrence of a specified character in a string.
strspn Returns the index of the first character in a string that does not match any character in a second string.
strstr Returns a pointer in a string that is identical to a second sub-string.

The string routines are implemented as functions and are prototyped in the string.h include file. They perform the following operations:

  • Copying strings
  • Appending one string to the end of another
  • Comparing two strings
  • Locating one or more characters from a specified set in a string

All string functions operate on null-terminated character strings. Use the buffer manipulation routines to work on non-terminated strings.