c正则匹配小计

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几个正则表达式（邮箱email，ipv4）匹配：

#include <sys/types.h>
#include <regex.h>
#include <stdio.h>

int main(int argc, char *argv[]){
        regex_t regex;
        int reti;
        char msgbuf[100];
const char *reg_exp = "^\\w+([-+.]\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*$";

//ipv4  '^((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])\\.){3}(25[0-5]|2[0-4][0-9]|1[09][0-9]|[1-9][0-9]|[0-9])$'

/* Compile regular expression */
        reti = regcomp(&regex, reg_exp, REG_EXTENDED);
        if( reti ){ fprintf(stderr, "Could not compile regex\n"); exit(1); }

/* Execute regular expression */
        reti = regexec(&regex, "[e-mail]", 0, NULL, 0);
        if( !reti ){
                puts("Match");
        }
        else if( reti == REG_NOMATCH ){
                puts("No match");
        }
        else{
                regerror(reti, &regex, msgbuf, sizeof(msgbuf));
                fprintf(stderr, "Regex match failed: %s\n", msgbuf);
                exit(1);
        }

/* Free compiled regular expression if you want to use the regex_t again */
        regfree(&regex);

        return 0;
}

完