我已经受不了每次用的时候去百度了,还百度不出来。。。。。
【数字字符串转换篇】
atof - convert a string to a double
#include <stdlib.h>
double atof(const char *nptr);
atoi, atol, atoll, atoq - convert a string to an integer
#include <stdlib.h>
int atoi(const char *nptr);
long atol(const char *nptr);
long long atoll(const char *nptr);
long long atoq(const char *nptr);
strtod, strtof, strtold - convert ASCII string to floating-point number
#include <stdlib.h>
double strtod(const char *nptr, char **endptr);
float strtof(const char *nptr, char **endptr);
long double strtold(const char *nptr, char **endptr);
strtoul, strtoull, strtouq - convert a string to an unsigned long integer
#include <stdlib.h>
unsigned long int strtoul(const char *nptr, char **endptr, int base);
unsigned long long int strtoull(const char *nptr, char **endptr, int base);
gcvt - convert a floating-point number to a string
#include <stdlib.h>
char *gcvt(double number, size_t ndigit, char *buf);
【字符串操作篇】
strtok, strtok_r - extract tokens from strings
#include <string.h>
char *strtok(char *str, const char *delim);
char *strtok_r(char *str, const char *delim, char **saveptr);
strcmp, strncmp - compare two strings
#include <string.h>
int strcmp(const char *s1, const char *s2);
int strncmp(const char *s1, const char *s2, size_t n);
strcasecmp, strncasecmp - compare two strings ignoring case
#include <strings.h>
int strcasecmp(const char *s1, const char *s2);
int strncasecmp(const char *s1, const char *s2, size_t n);
【网络字节篇】
htonl, htons, ntohl, ntohs - convert values between host and network byte order
#include <arpa/inet.h>
uint32_t htonl(uint32_t hostlong);
uint16_t htons(uint16_t hostshort);
uint32_t ntohl(uint32_t netlong);
uint16_t ntohs(uint16_t netshort);
【输出篇】
printf, fprintf, sprintf, snprintf, vprintf, vfprintf, vsprintf, vsnprintf - formatted output conversion
#include <stdio.h>
int printf(const char *format, ...);
int fprintf(FILE *stream, const char *format, ...);
int sprintf(char *str, const char *format, ...);
int snprintf(char *str, size_t size, const char *format, ...);
#include <stdarg.h>
int vprintf(const char *format, va_list ap);
int vfprintf(FILE *stream, const char *format, va_list ap);
int vsprintf(char *str, const char *format, va_list ap);
int vsnprintf(char *str, size_t size, const char *format, va_list ap);