Segmentation fault when reading file in C
I'm trying to read from a file. My program reads the first line correctly, but at the second line I get a segmentation fault and I have no idea why that is.
Here's my code (sorry it's in Hungarian) :
FILE *fp = fopen (fajlnev, "r");
if (fp == NULL) {
perror("Fájl megnyitása sikertelen");
return;
}
char tmp [21];
strcpy(tmp,nev);
strcpy(pj->nev,"");
char buf1, buf2, buf3;
fscanf(fp, "%c%c%c", &buf1, &buf2, &buf3);
while (strcmp(pj->nev, tmp)!=0 ) {
fscanf(fp, "%s %d %dn", pj->nev, &(pj->meret), &(pj->pontszam));
for(int i=0; i<pj->meret; i++) {
for(int k=0; k<pj->meret; k++) {
fscanf(fp, "%u", &(pj->foldek[i][k].n));
fscanf(fp, "%d", &(pj->foldek[i][k].allapot));
fscanf(fp, "%ld", (long *)&(pj->foldek[i][k].ido));
printf("hiba");
}
}
fscanf(fp, "n");
}
pj->foldek[i][j].n is an enumerated type, allapot is an integer and ido is time_t
I'd be really grateful if you could help me! :)
file segmentation-fault scanf
edited Nov 24 '18 at 9:58
common sense
2,54841625
asked Nov 24 '18 at 8:39
PetraPetra
11
add a comment |
I'm trying to read from a file. My program reads the first line correctly, but at the second line I get a segmentation fault and I have no idea why that is.
Here's my code (sorry it's in Hungarian) :
FILE *fp = fopen (fajlnev, "r");
if (fp == NULL) {
perror("Fájl megnyitása sikertelen");
return;
}
char tmp [21];
strcpy(tmp,nev);
strcpy(pj->nev,"");
char buf1, buf2, buf3;
fscanf(fp, "%c%c%c", &buf1, &buf2, &buf3);
while (strcmp(pj->nev, tmp)!=0 ) {
fscanf(fp, "%s %d %dn", pj->nev, &(pj->meret), &(pj->pontszam));
for(int i=0; i<pj->meret; i++) {
for(int k=0; k<pj->meret; k++) {
fscanf(fp, "%u", &(pj->foldek[i][k].n));
fscanf(fp, "%d", &(pj->foldek[i][k].allapot));
fscanf(fp, "%ld", (long *)&(pj->foldek[i][k].ido));
printf("hiba");
}
}
fscanf(fp, "n");
}
pj->foldek[i][j].n is an enumerated type, allapot is an integer and ido is time_t
I'd be really grateful if you could help me! :)
file segmentation-fault scanf
edited Nov 24 '18 at 9:58
common sense
2,54841625
asked Nov 24 '18 at 8:39
PetraPetra
11
Hi Petra, you are not using any debugger obviously, but there's something easy to do. Try to replace the two strcpy calls strcpy(tmp,nev); strcpy(pj->nev,""); with memcpy or with strncpy calls and see if you can fix it this way.
– Krassi Em
Dec 1 '18 at 17:41
add a comment |
I'm trying to read from a file. My program reads the first line correctly, but at the second line I get a segmentation fault and I have no idea why that is.
Here's my code (sorry it's in Hungarian) :
FILE *fp = fopen (fajlnev, "r");
if (fp == NULL) {
perror("Fájl megnyitása sikertelen");
return;
}
char tmp [21];
strcpy(tmp,nev);
strcpy(pj->nev,"");
char buf1, buf2, buf3;
fscanf(fp, "%c%c%c", &buf1, &buf2, &buf3);
while (strcmp(pj->nev, tmp)!=0 ) {
fscanf(fp, "%s %d %dn", pj->nev, &(pj->meret), &(pj->pontszam));
for(int i=0; i<pj->meret; i++) {
for(int k=0; k<pj->meret; k++) {
fscanf(fp, "%u", &(pj->foldek[i][k].n));
fscanf(fp, "%d", &(pj->foldek[i][k].allapot));
fscanf(fp, "%ld", (long *)&(pj->foldek[i][k].ido));
printf("hiba");
}
}
fscanf(fp, "n");
}
pj->foldek[i][j].n is an enumerated type, allapot is an integer and ido is time_t
I'd be really grateful if you could help me! :)
file segmentation-fault scanf
edited Nov 24 '18 at 9:58
common sense
2,54841625
asked Nov 24 '18 at 8:39
PetraPetra
11
I'm trying to read from a file. My program reads the first line correctly, but at the second line I get a segmentation fault and I have no idea why that is.
Here's my code (sorry it's in Hungarian) :
FILE *fp = fopen (fajlnev, "r");
if (fp == NULL) {
perror("Fájl megnyitása sikertelen");
return;
}
char tmp [21];
strcpy(tmp,nev);
strcpy(pj->nev,"");
char buf1, buf2, buf3;
fscanf(fp, "%c%c%c", &buf1, &buf2, &buf3);
while (strcmp(pj->nev, tmp)!=0 ) {
fscanf(fp, "%s %d %dn", pj->nev, &(pj->meret), &(pj->pontszam));
for(int i=0; i<pj->meret; i++) {
for(int k=0; k<pj->meret; k++) {
fscanf(fp, "%u", &(pj->foldek[i][k].n));
fscanf(fp, "%d", &(pj->foldek[i][k].allapot));
fscanf(fp, "%ld", (long *)&(pj->foldek[i][k].ido));
printf("hiba");
}
}
fscanf(fp, "n");
}
pj->foldek[i][j].n is an enumerated type, allapot is an integer and ido is time_t
I'd be really grateful if you could help me! :)
file segmentation-fault scanf
file segmentation-fault scanf
edited Nov 24 '18 at 9:58
common sense
2,54841625
asked Nov 24 '18 at 8:39
PetraPetra
11
edited Nov 24 '18 at 9:58
common sense
2,54841625
asked Nov 24 '18 at 8:39
PetraPetra
11
edited Nov 24 '18 at 9:58
common sense
2,54841625
edited Nov 24 '18 at 9:58
common sense
2,54841625
edited Nov 24 '18 at 9:58
common sense
2,54841625
2,54841625
asked Nov 24 '18 at 8:39
PetraPetra
11
asked Nov 24 '18 at 8:39
PetraPetra
11
asked Nov 24 '18 at 8:39
PetraPetra
11
11
Hi Petra, you are not using any debugger obviously, but there's something easy to do. Try to replace the two strcpy calls strcpy(tmp,nev); strcpy(pj->nev,""); with memcpy or with strncpy calls and see if you can fix it this way.
– Krassi Em
Dec 1 '18 at 17:41
add a comment |
Hi Petra, you are not using any debugger obviously, but there's something easy to do. Try to replace the two strcpy calls strcpy(tmp,nev); strcpy(pj->nev,""); with memcpy or with strncpy calls and see if you can fix it this way.
– Krassi Em
Dec 1 '18 at 17:41
Hi Petra, you are not using any debugger obviously, but there's something easy to do. Try to replace the two strcpy calls strcpy(tmp,nev); strcpy(pj->nev,""); with memcpy or with strncpy calls and see if you can fix it this way.
– Krassi Em
Dec 1 '18 at 17:41
Hi Petra, you are not using any debugger obviously, but there's something easy to do. Try to replace the two strcpy calls strcpy(tmp,nev); strcpy(pj->nev,""); with memcpy or with strncpy calls and see if you can fix it this way.
– Krassi Em
Dec 1 '18 at 17:41
add a comment |
1 Answer
1
active
oldest
votes
Please alter the while loop:
while (!feof(fp) && strcmp(pj->nev, tmp)!=0 )
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Please alter the while loop:
while (!feof(fp) && strcmp(pj->nev, tmp)!=0 )
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
add a comment |
Please alter the while loop:
while (!feof(fp) && strcmp(pj->nev, tmp)!=0 )
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
add a comment |
Please alter the while loop:
while (!feof(fp) && strcmp(pj->nev, tmp)!=0 )
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
Please alter the while loop:
while (!feof(fp) && strcmp(pj->nev, tmp)!=0 )
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
answered Dec 1 '18 at 17:46
Krassi EmKrassi Em
1667
1667
add a comment |
add a comment |
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Hi Petra, you are not using any debugger obviously, but there's something easy to do. Try to replace the two strcpy calls strcpy(tmp,nev); strcpy(pj->nev,""); with memcpy or with strncpy calls and see if you can fix it this way.
– Krassi Em
Dec 1 '18 at 17:41