linux c实现的提取文件名的小程序

/*@author etangyushan
 *工作中很多时候会和文件名打交道，有时候只需要文件名称，就写了这么一个小程序
 *这个函数实现了把一个文件的绝对路径和后缀去除，只留下文件名的功能
 * */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

//找到最后的slash(/)
int last_mark (char *str, char mark)
{
    int site = 0;  
    int count = 0;
    while (site <= strlen(str))
    {
        if (str[site++] == mark)
        {
         count = site; 
        }
    }
    return count;
}

//找到第一个dot(.)
int first_mark (char *str, char mark, int num)
{
    int count = num;
    while (1)  
    {
        if (str[count++] == mark)
        {
            break;
        }
    }
    return count; 
}

/* 从文件全名中把文件名提取出来,有后缀 */
int substr_suffix (char *srcstr, char *decstr, int slash)
{
    int i = 0;
    int size = strlen(srcstr);
    for (i=0; i<size; i++)
    {
        decstr[i] = srcstr[slash++];
    }
}

/* 从文件全名中把文件名提取出来,去除后缀 */
int substr (char *srcstr, char *decstr, int lastslash, int firstdot)
{
    int i = 0;
    //printf("last=%d,first=%d\n", lastslash, firstdot);
    //printf("size=%d\n", firstdot-lastslash);
    int size = firstdot-lastslash-1;
    for (i=0; i<size; i++)
    {
        //printf("...%c...\n",srcstr[lastslash]);
        decstr[i] = srcstr[lastslash++];
    }
}

//测试
int main()
{
    char *file = "/root/etc/init.d/myte123456789abcedefadfaefsa1234.c";
    char filename[256] = {};
    char filename_nosuffix[256] = {};

    int lastnum = last_mark (file, '/');
    int firstnum = first_mark (file, '.', lastnum);

    substr_suffix (file, filename, lastnum);
    printf ("filename = %s\n", filename);

    substr (file, filename_nosuffix, lastnum, firstnum);
    printf ("filename no suffix = %s\n", filename_nosuffix);
}