cstring - C - How to read a string line by line? -

in c program, have string want process 1 line @ time, ideally saving each line string, doing want said string, , repeating. have no idea how accomplished, though.

i thinking of using sscanf. there "read pointer" present in sscanf there if reading file? alternative doing this?

here's example of how can efficiently, if allowed write long string:

#include <stdio.h> #include <string.h>  int main(int argc, char ** argv) {    char longstring[] = "this long string.\nit has multiple lines of text in it.\nwe want examine each of these lines separately.\nso that.";    char * curline = longstring;    while(curline)    {       char * nextline = strchr(curline, '\n');       if (nextline) *nextline = '\0';  // temporarily terminate current line       printf("curline=[%s]\n", curline);       if (nextline) *nextline = '\n';  // restore newline-char, tidy           curline = nextline ? (nextline+1) : null;    }    return 0; } 

if you're not allowed write long string, you'll need make temporary string each line instead, in order have per-line string nul terminated. this:

#include <stdio.h> #include <stdlib.h> #include <string.h>  int main(int argc, char ** argv) {    const char longstring[] = "this long string.\nit has multiple lines of text in it.\nwe want examine each of these lines separately.\nso that.";    const char * curline = longstring;    while(curline)    {       const char * nextline = strchr(curline, '\n');       int curlinelen = nextline ? (nextline-curline) : strlen(curline);       char * tempstr = (char *) malloc(curlinelen+1);       if (tempstr)       {          memcpy(tempstr, curline, curlinelen);          tempstr[curlinelen] = '\0';  // nul-terminate!          printf("tempstr=[%s]\n", tempstr);          free(tempstr);       }       else printf("malloc() failed!?\n");        curline = nextline ? (nextline+1) : null;    }    return 0; }