Filling char array with snprintf()
-3
I am trying to fill a char array with values under conditions. The problem is I can not use snprintf() not properly.
char staedte[MAX_LAENGE_ARR][MAX_LAENGE_STR];
char laender[MAX_LAENGE_ARR][MAX_LAENGE_STR];
int bewohner[MAX_LAENGE_ARR];
char *p = (char*) malloc(len);
if (p == NULL){
perror("malloc failed while allocating an array of chars.");
exit(1);
}
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
}
}
free(p);
}
c
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
|
show 8 more comments
-3
I am trying to fill a char array with values under conditions. The problem is I can not use snprintf() not properly.
char staedte[MAX_LAENGE_ARR][MAX_LAENGE_STR];
char laender[MAX_LAENGE_ARR][MAX_LAENGE_STR];
int bewohner[MAX_LAENGE_ARR];
char *p = (char*) malloc(len);
if (p == NULL){
perror("malloc failed while allocating an array of chars.");
exit(1);
}
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
}
}
free(p);
}
c
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
1
bewohner is integer but others are char.
– aomerk
Oct 25 '18 at 16:18
2
Oh duh, eyes deceived me. Please add an example of the file you're reading, the output you expect to see and the output you are currently seeing
– Tormund Giantsbane
Oct 25 '18 at 16:22
i edited my question. my problem is about the usage of char array and snprintf()
– aomerk
Oct 25 '18 at 16:25
2
Please try to post a Minimal, Complete, and Verifiable example. There's a lot of code here that isn't relevant to the problem. I think it will be easier for you to find out what's wrong if you strip the code right down to the bare minimum.
– Tim Randall
Oct 25 '18 at 16:27
1
What doesread_filereturn? Usually snprintf is used like:char p[256]; const size_t p_size = 256; const size_t p_pos = 0;and thenp_pos = snprintf(&p[p_pos], p_size - p_pos, "some string");. PassingMAX_LAENGE_STRtopwhenpismalloc(len);may overflow. snprintf returns the number of characters written, so you can know when to start the next snprint.
– Kamil Cuk
Oct 25 '18 at 16:57
|
show 8 more comments
-3
-3
-3
I am trying to fill a char array with values under conditions. The problem is I can not use snprintf() not properly.
char staedte[MAX_LAENGE_ARR][MAX_LAENGE_STR];
char laender[MAX_LAENGE_ARR][MAX_LAENGE_STR];
int bewohner[MAX_LAENGE_ARR];
char *p = (char*) malloc(len);
if (p == NULL){
perror("malloc failed while allocating an array of chars.");
exit(1);
}
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
}
}
free(p);
}
c
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
I am trying to fill a char array with values under conditions. The problem is I can not use snprintf() not properly.
char staedte[MAX_LAENGE_ARR][MAX_LAENGE_STR];
char laender[MAX_LAENGE_ARR][MAX_LAENGE_STR];
int bewohner[MAX_LAENGE_ARR];
char *p = (char*) malloc(len);
if (p == NULL){
perror("malloc failed while allocating an array of chars.");
exit(1);
}
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
}
}
free(p);
}
c
c
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
edited Dec 31 '18 at 9:26
aomerk
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
asked Oct 25 '18 at 16:10
aomerkaomerk
19015
19015
1
bewohner is integer but others are char.
– aomerk
Oct 25 '18 at 16:18
2
Oh duh, eyes deceived me. Please add an example of the file you're reading, the output you expect to see and the output you are currently seeing
– Tormund Giantsbane
Oct 25 '18 at 16:22
i edited my question. my problem is about the usage of char array and snprintf()
– aomerk
Oct 25 '18 at 16:25
2
Please try to post a Minimal, Complete, and Verifiable example. There's a lot of code here that isn't relevant to the problem. I think it will be easier for you to find out what's wrong if you strip the code right down to the bare minimum.
– Tim Randall
Oct 25 '18 at 16:27
1
What doesread_filereturn? Usually snprintf is used like:char p[256]; const size_t p_size = 256; const size_t p_pos = 0;and thenp_pos = snprintf(&p[p_pos], p_size - p_pos, "some string");. PassingMAX_LAENGE_STRtopwhenpismalloc(len);may overflow. snprintf returns the number of characters written, so you can know when to start the next snprint.
– Kamil Cuk
Oct 25 '18 at 16:57
|
show 8 more comments
1
bewohner is integer but others are char.
– aomerk
Oct 25 '18 at 16:18
2
Oh duh, eyes deceived me. Please add an example of the file you're reading, the output you expect to see and the output you are currently seeing
– Tormund Giantsbane
Oct 25 '18 at 16:22
i edited my question. my problem is about the usage of char array and snprintf()
– aomerk
Oct 25 '18 at 16:25
2
Please try to post a Minimal, Complete, and Verifiable example. There's a lot of code here that isn't relevant to the problem. I think it will be easier for you to find out what's wrong if you strip the code right down to the bare minimum.
– Tim Randall
Oct 25 '18 at 16:27
1
What doesread_filereturn? Usually snprintf is used like:char p[256]; const size_t p_size = 256; const size_t p_pos = 0;and thenp_pos = snprintf(&p[p_pos], p_size - p_pos, "some string");. PassingMAX_LAENGE_STRtopwhenpismalloc(len);may overflow. snprintf returns the number of characters written, so you can know when to start the next snprint.
– Kamil Cuk
Oct 25 '18 at 16:57
1
1
bewohner is integer but others are char.
– aomerk
Oct 25 '18 at 16:18
bewohner is integer but others are char.
– aomerk
Oct 25 '18 at 16:18
2
2
Oh duh, eyes deceived me. Please add an example of the file you're reading, the output you expect to see and the output you are currently seeing
– Tormund Giantsbane
Oct 25 '18 at 16:22
Oh duh, eyes deceived me. Please add an example of the file you're reading, the output you expect to see and the output you are currently seeing
– Tormund Giantsbane
Oct 25 '18 at 16:22
i edited my question. my problem is about the usage of char array and snprintf()
– aomerk
Oct 25 '18 at 16:25
i edited my question. my problem is about the usage of char array and snprintf()
– aomerk
Oct 25 '18 at 16:25
2
2
Please try to post a Minimal, Complete, and Verifiable example. There's a lot of code here that isn't relevant to the problem. I think it will be easier for you to find out what's wrong if you strip the code right down to the bare minimum.
– Tim Randall
Oct 25 '18 at 16:27
Please try to post a Minimal, Complete, and Verifiable example. There's a lot of code here that isn't relevant to the problem. I think it will be easier for you to find out what's wrong if you strip the code right down to the bare minimum.
– Tim Randall
Oct 25 '18 at 16:27
1
1
What does
read_file return? Usually snprintf is used like: char p[256]; const size_t p_size = 256; const size_t p_pos = 0; and then p_pos = snprintf(&p[p_pos], p_size - p_pos, "some string");. Passing MAX_LAENGE_STR to p when p is malloc(len); may overflow. snprintf returns the number of characters written, so you can know when to start the next snprint.– Kamil Cuk
Oct 25 '18 at 16:57
What does
read_file return? Usually snprintf is used like: char p[256]; const size_t p_size = 256; const size_t p_pos = 0; and then p_pos = snprintf(&p[p_pos], p_size - p_pos, "some string");. Passing MAX_LAENGE_STR to p when p is malloc(len); may overflow. snprintf returns the number of characters written, so you can know when to start the next snprint.– Kamil Cuk
Oct 25 '18 at 16:57
|
show 8 more comments
2 Answers
2
active
oldest
votes
0
snprintf() returns the number of bytes that it wrote to the string. You can use this to increment the position where you write the next line.
int offset = 0;
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
int written = snprintf(p + offset, len - offset, Die Stadt %s hat %d Einwohner. n", staedte[i], bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
offset += written;
}
}
I'm not sure why you're calling snprintf() twice. I removed the one that just writes to p.
Since the length of the p string is len bytes, you should use that when specifying the maximum amount to write in snprintf(), not MAX_LANGE_STR. You have to subtract offset from it, since each write is further in the string and there's less room left after it.
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
add a comment |
1
regarding:
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
}
the first call to snprintf() keeps overlaying the first entry in the p array
suggest:
char buffer[MAX_LAENGE_STR+1];
p[0] = '';
then in the loop
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf( buffer, MAX_LAENGE_STR, "Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
strcat( p, buffer );
printf("%s : %dn",staedte[i] , bewohner[i]);
}
I'll leave it to you to add the checking that the buffer p is not overflowed.
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
pis not an array of pointers, it's a pointer to achararray.
– Barmar
Oct 25 '18 at 17:57
1
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
@aomerk, no, the use ofstrcat()will place the data at the next available location inp
– user3629249
Oct 25 '18 at 20:54
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
|
show 3 more comments
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
snprintf() returns the number of bytes that it wrote to the string. You can use this to increment the position where you write the next line.
int offset = 0;
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
int written = snprintf(p + offset, len - offset, Die Stadt %s hat %d Einwohner. n", staedte[i], bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
offset += written;
}
}
I'm not sure why you're calling snprintf() twice. I removed the one that just writes to p.
Since the length of the p string is len bytes, you should use that when specifying the maximum amount to write in snprintf(), not MAX_LANGE_STR. You have to subtract offset from it, since each write is further in the string and there's less room left after it.
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
add a comment |
0
snprintf() returns the number of bytes that it wrote to the string. You can use this to increment the position where you write the next line.
int offset = 0;
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
int written = snprintf(p + offset, len - offset, Die Stadt %s hat %d Einwohner. n", staedte[i], bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
offset += written;
}
}
I'm not sure why you're calling snprintf() twice. I removed the one that just writes to p.
Since the length of the p string is len bytes, you should use that when specifying the maximum amount to write in snprintf(), not MAX_LANGE_STR. You have to subtract offset from it, since each write is further in the string and there's less room left after it.
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
add a comment |
0
0
0
snprintf() returns the number of bytes that it wrote to the string. You can use this to increment the position where you write the next line.
int offset = 0;
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
int written = snprintf(p + offset, len - offset, Die Stadt %s hat %d Einwohner. n", staedte[i], bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
offset += written;
}
}
I'm not sure why you're calling snprintf() twice. I removed the one that just writes to p.
Since the length of the p string is len bytes, you should use that when specifying the maximum amount to write in snprintf(), not MAX_LANGE_STR. You have to subtract offset from it, since each write is further in the string and there's less room left after it.
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
snprintf() returns the number of bytes that it wrote to the string. You can use this to increment the position where you write the next line.
int offset = 0;
for (int i = 0; i < MAX_LAENGE_ARR; i++) {
if(strcmp(bundesland,laender[i]) == 0 && bewohner[i] >= anzahl){
int written = snprintf(p + offset, len - offset, Die Stadt %s hat %d Einwohner. n", staedte[i], bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
offset += written;
}
}
I'm not sure why you're calling snprintf() twice. I removed the one that just writes to p.
Since the length of the p string is len bytes, you should use that when specifying the maximum amount to write in snprintf(), not MAX_LANGE_STR. You have to subtract offset from it, since each write is further in the string and there's less room left after it.
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
answered Oct 25 '18 at 18:01
BarmarBarmar
426k36249351
426k36249351
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
add a comment |
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
I wasnt actually calling it twice, I was just showing two different ways I was trying :)
– aomerk
Oct 25 '18 at 19:15
add a comment |
1
regarding:
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
}
the first call to snprintf() keeps overlaying the first entry in the p array
suggest:
char buffer[MAX_LAENGE_STR+1];
p[0] = '';
then in the loop
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf( buffer, MAX_LAENGE_STR, "Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
strcat( p, buffer );
printf("%s : %dn",staedte[i] , bewohner[i]);
}
I'll leave it to you to add the checking that the buffer p is not overflowed.
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
pis not an array of pointers, it's a pointer to achararray.
– Barmar
Oct 25 '18 at 17:57
1
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
@aomerk, no, the use ofstrcat()will place the data at the next available location inp
– user3629249
Oct 25 '18 at 20:54
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
|
show 3 more comments
1
regarding:
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
}
the first call to snprintf() keeps overlaying the first entry in the p array
suggest:
char buffer[MAX_LAENGE_STR+1];
p[0] = '';
then in the loop
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf( buffer, MAX_LAENGE_STR, "Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
strcat( p, buffer );
printf("%s : %dn",staedte[i] , bewohner[i]);
}
I'll leave it to you to add the checking that the buffer p is not overflowed.
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
pis not an array of pointers, it's a pointer to achararray.
– Barmar
Oct 25 '18 at 17:57
1
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
@aomerk, no, the use ofstrcat()will place the data at the next available location inp
– user3629249
Oct 25 '18 at 20:54
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
|
show 3 more comments
1
1
1
regarding:
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
}
the first call to snprintf() keeps overlaying the first entry in the p array
suggest:
char buffer[MAX_LAENGE_STR+1];
p[0] = '';
then in the loop
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf( buffer, MAX_LAENGE_STR, "Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
strcat( p, buffer );
printf("%s : %dn",staedte[i] , bewohner[i]);
}
I'll leave it to you to add the checking that the buffer p is not overflowed.
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
regarding:
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf(p,MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
snprintf(&p[i],MAX_LAENGE_STR,"Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
printf("%s : %dn",staedte[i] , bewohner[i]);
}
the first call to snprintf() keeps overlaying the first entry in the p array
suggest:
char buffer[MAX_LAENGE_STR+1];
p[0] = '';
then in the loop
if( strcmp( bundesland,laender[i] ) == 0 && bewohner[i] >= anzahl)
{
snprintf( buffer, MAX_LAENGE_STR, "Die Stadt %s hat %d Einwohner. n", staedte[i],bewohner[i]);
strcat( p, buffer );
printf("%s : %dn",staedte[i] , bewohner[i]);
}
I'll leave it to you to add the checking that the buffer p is not overflowed.
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
edited Oct 25 '18 at 18:15
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
answered Oct 25 '18 at 17:56
user3629249user3629249
11.1k11014
11.1k11014
pis not an array of pointers, it's a pointer to achararray.
– Barmar
Oct 25 '18 at 17:57
1
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
@aomerk, no, the use ofstrcat()will place the data at the next available location inp
– user3629249
Oct 25 '18 at 20:54
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
|
show 3 more comments
pis not an array of pointers, it's a pointer to achararray.
– Barmar
Oct 25 '18 at 17:57
1
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
@aomerk, no, the use ofstrcat()will place the data at the next available location inp
– user3629249
Oct 25 '18 at 20:54
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
p is not an array of pointers, it's a pointer to a char array.– Barmar
Oct 25 '18 at 17:57
p is not an array of pointers, it's a pointer to a char array.– Barmar
Oct 25 '18 at 17:57
1
1
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
@Barmar. Ok, I'll modify my answer accordingly
– user3629249
Oct 25 '18 at 18:01
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
but this way, there is always a empty line at the beginning.
– aomerk
Oct 25 '18 at 20:25
@aomerk, no, the use of
strcat() will place the data at the next available location in p– user3629249
Oct 25 '18 at 20:54
@aomerk, no, the use of
strcat() will place the data at the next available location in p– user3629249
Oct 25 '18 at 20:54
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
@aomerk, I have no idea what the 'Bug' is referring to. The question states that there are 8 lines to be printed
– user3629249
Oct 25 '18 at 21:00
|
show 3 more comments
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1
bewohner is integer but others are char.
– aomerk
Oct 25 '18 at 16:18
2
Oh duh, eyes deceived me. Please add an example of the file you're reading, the output you expect to see and the output you are currently seeing
– Tormund Giantsbane
Oct 25 '18 at 16:22
i edited my question. my problem is about the usage of char array and snprintf()
– aomerk
Oct 25 '18 at 16:25
2
Please try to post a Minimal, Complete, and Verifiable example. There's a lot of code here that isn't relevant to the problem. I think it will be easier for you to find out what's wrong if you strip the code right down to the bare minimum.
– Tim Randall
Oct 25 '18 at 16:27
1
What does
read_filereturn? Usually snprintf is used like:char p[256]; const size_t p_size = 256; const size_t p_pos = 0;and thenp_pos = snprintf(&p[p_pos], p_size - p_pos, "some string");. PassingMAX_LAENGE_STRtopwhenpismalloc(len);may overflow. snprintf returns the number of characters written, so you can know when to start the next snprint.– Kamil Cuk
Oct 25 '18 at 16:57