why does fgets() keep skipping last letter when I dont have an empty line at the end?

Question

I want to get every line and put it in my array. This works when I have an empty line at the end of the file, but I need to be able to process all lines without having a line at the end. When I read the file the x is missing at the end of ax on the last line. This is the file used:

read ax
mul 2 ax
print ax

the file I get with my code:
read ax
mul 2 ax
print a

This is what I have at the moment. How can I fix this?

int row = 100;
int columns = 100;
char operation[row][columns];
FILE *fp = fopen(argv[1],"r");
//populates matrix of assembly code
while(fgets(operation[i],columns, fp)!=NULL){
  operation[i][strlen(operation[i])-1] = '\0';
  i++;
} numberOfLines = i;

for(int i = 0; i < numberOfLines;i++){
   printf("%s\n",operation[i]);

}

You're setting the last character of the line that was read to 0 without making sure it's a newline first... — Shawn, Nov 21 '20 at 06:31
[Your step 3 is wrong](https://stackoverflow.com/a/60551717/918959) — Antti Haapala -- Слава Україні, Nov 21 '20 at 06:59

Fredrik · Accepted Answer · 2020-11-21T06:54:50.283

1

operation[i][strcspn(operation[i], "\r\n")] = '\0';

This will set the first '\r' or '\n' to '\0'

https://www.tutorialspoint.com/c_standard_library/c_function_strcspn.htm

edited Nov 21 '20 at 06:54

answered Nov 21 '20 at 06:32

Fredrik

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can you elaborate please? – Julian Romero Nov 21 '20 at 06:34
where would this work? – Julian Romero Nov 21 '20 at 06:41
@Julian what do you mean? It will work with any string. – Fredrik Nov 21 '20 at 06:42
do i put this after my operation, or do I replace it? Cause when i replaced it with my line i got an error – Julian Romero Nov 21 '20 at 06:44
@Julian did you include ? – Fredrik Nov 21 '20 at 06:45
You replace your line with this one. – Fredrik Nov 21 '20 at 06:45
oh okay i got it to work thanks! – Julian Romero Nov 21 '20 at 06:49

why does fgets() keep skipping last letter when I dont have an empty line at the end?

1 Answers1