Cx51 Standard Library Program Attribute Description

String Operations STRING.H 

strcat concatenates two stringsstrchr
reentrant returns a pointer to the first occurrence of a specified character in one stringstrcmp reentrant
compares two stringsstrcpy
reentrant copies one string to anotherstrcspn returns the index of the first character
in one string that matches any character in the second stringstrlen reentrant string lengthstrncat concatenates a specified number of characters from one string to anotherstrncmp compares a specified number of characters from two stringsstrncpy copies a specified number of characters from one string to anotherstrpbrk returns a pointer to the first character in one string that matches any character in the second stringstrpos reentrant returns the index of the first occurrence of a specified character in a stringstrrchr reentrant returns a pointer to the last occurrence of a specified character in a stringstrrpbrk returns a pointer to the last character in one string that matches any character in the second stringstrrpos reentrant returns the index of the last occurrence of a specified character in a stringstrspn returns the index of the first character in one string that does not match any character in the second stringstrstr returns a pointer to a substring in one string that is the same as another

Buffer Operations

STRING.H
memchr Reentrant Returns the pointer to the first occurrence of a specified character in a buffer
memcmp Reentrant Compares a given number of characters from two different buffers
memcpy Reentrant Copies a specified number of data from one buffer to another memmove
Reentrant Copies a specified number of data from one buffer to another memset
Reentrant Initializes a specified number of data bytes in a buffer to a specified character value

Character conversion and classification CTYPE.H
 isalnum Reentrant Whether it is an alphabetic or numeric character
isalpha Reentrant Whether it is an alphabetic character
iscntrl Reentrant Whether it is a control character
isdigit Reentrant Whether it is a decimal number
isgraph Reentrant Whether it is a printable character other than space
islower Reentrant Whether it is a lowercase alphabetic character
isprint Reentrant Whether it is a printable character
ispunct Reentrant Whether it is a punctuation character
isspace Reentrant Whether it is a space
isupper Reentrant Whether it is an uppercase alphabetic character
isxdigit Reentrant Whether it is a hexadecimal number
toascii Reentrant Convert a character to an ASCII code toint Reentrant
Convert a hexadecimal number to a decimal number
tolower Reentrant Test a character if it is uppercase and convert it to lowercase
_tolower Reentrant Unconditionally Convert a character to lowercase
toupper Reentrant Test a character if it is uppercase and convert it to lowercase
_toupper Reentrant Unconditionally Convert a character to uppercase

Data conversionSTDLIB.H 
abs Reentrant to get the absolute value of an integer typeatof
/atof517 Convert a string to a floatatoi
Convert a string to an intatol
Convert a string to a longcabs
Reentrant to get the absolute value of a character typelabs Reentrant to
get the absolute value of a long typestrtod
/strtod Convert a string to a floatstrtol
Convert a string to a longstrtoul
Convert a string to an unsigned long