#cat bb.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>

#define KEYVALLEN 100

/*   Delete left side blank   */
char * l_trim(char * szOutput, const char *szInput)
{
    assert(szInput != NULL);
    assert(szOutput != NULL);
    assert(szOutput != szInput);
    for(NULL; *szInput != ‘\0‘ && isspace(*szInput); ++szInput){
        ;
    }
    return strcpy(szOutput, szInput);
}

/*   Delete right side blank   */
char *r_trim(char *szOutput, const char *szInput)
{
    char *p = NULL;
    assert(szInput != NULL);
    assert(szOutput != NULL);
    assert(szOutput != szInput);
    strcpy(szOutput, szInput);
    for(p = szOutput + strlen(szOutput) - 1; p >= szOutput && isspace(*p); --p){
        ;
    }
    *(++p) = ‘\0‘  ;
    return szOutput;
}

/*   Delete both side blank   */
char * a_trim(char * szOutput, const char * szInput)
{
    char *p = NULL;
    assert(szInput != NULL);
    assert(szOutput != NULL);
    l_trim(szOutput, szInput);
    for (p = szOutput + strlen(szOutput) - 1;p >= szOutput && isspace(*p); --p){
        ;
    }
    *(++p) = ‘\0‘;
    return szOutput;
}


int GetProfileString(char *profile, char *AppName, char *KeyName, char *KeyVal )
{
    char appname[32],keyname[32];
    char *buf,*c;
    char buf_i[KEYVALLEN], buf_o[KEYVALLEN];
    FILE *fp;
    int found=0;   /* 1 AppName 2 KeyName */
    if((fp=fopen( profile, "r"))==NULL){
    printf("openfile [%s] error [%s]\n", profile, strerror(errno));
        return(-1);
    }
    fseek(fp, 0, SEEK_SET );
    memset(appname, 0, sizeof(appname) );
    sprintf(appname, "[%s]", AppName );

    while(! feof(fp) && fgets( buf_i, KEYVALLEN, fp )!=NULL){
        l_trim(buf_o, buf_i);
        if( strlen(buf_o) <= 0 )
            continue  ;
        buf = NULL;
        buf = buf_o;

        if(found == 0){
            if( buf[0] != ‘[‘ ) {
                continue  ;
            } else if (strncmp(buf,appname, strlen(appname))==0){
                found = 1;
                continue;
            }

        } else if( found == 1 ) {
            if (buf[0] == ‘#‘) {
                continue  ;
            } else if ( buf[0] == ‘[‘ ) {
                break;
            } else {
                if( (c = (char *) strchr(buf, ‘=‘)) == NULL )
                    continue  ;
                memset( keyname, 0, sizeof(keyname) );

                sscanf(buf, "%[^=|^ |^\t]", keyname);
                if(strcmp(keyname, KeyName) == 0 ) {
                    sscanf( ++c, "%[^\n]", KeyVal);
                    char *KeyVal_o = (char *) malloc(strlen (KeyVal) + 1);
                    if(KeyVal_o != NULL) {
                        memset(KeyVal_o, 0, sizeof(KeyVal_o));
                        a_trim(KeyVal_o, KeyVal);
                    if(KeyVal_o && strlen(KeyVal_o) > 0)
                        strcpy(KeyVal, KeyVal_o);
                        free(KeyVal_o);
                        KeyVal_o = NULL;
                    }
                    found = 2;
                    break;
                } else {
                    continue  ;
                }
            }
        }
    }
    fclose (fp);
    if (found == 2 )
        return(0);
    else
        return(-1);
}

void main()
{
    char ip[16];
    char dev[10];
    GetProfileString("./bb.txt", "cls_server", "ip", ip);
    GetProfileString("./bb.txt", "device", "dev", dev);
    printf("%s\n", ip);
    printf("%s\n", dev);
}
 

#cat bb.txt
[cls_server]
#配置文件等號左右可以有空格也可以沒有
ip=192.16.31.2

[device]
dev=sda

C解析config