Im getting a lineshift when trying to build a string - c

Question

Im trying to build a string to call a script with args, and one of the args is read from a file but im getting a lineshift and the output is like this
/home/glennwiz/develop/c/SnuPort/ExpGetConfig.sh xogs1a 3/37
> lastConfig.txt
i want the 3/37 and > lastConfig to be on the same line.
this is my code.
char getConfig[100] = "/home/glennwiz/develop/c/SnuPort/ExpGetConfig.sh ";
char filedumpto[50] = " > lastConfig.txt";
FILE* file = fopen("rport.txt","r");
if(file == NULL)
{
return NULL;
}
fseek(file, 0, SEEK_END);
long int size = ftell(file);
rewind(file);
char* port = calloc(size, 1);
fread(port,1,size,file);
strcat(getConfig, argv[1]);
strcat(getConfig, port);
strcat(getConfig, filedumpto);
printf(getConfig);
//system(getConfig);
return 0;
edit
i dumped the output to a file and opened it in vim to see and it sends a ^M after the variable, which is enter i believe? why does it do this iv tried the solutions under this post but its not working.
tester port print!!!!
/home/glennwiz/develop/c/SnuPort/ExpGetConfig.sh randa1ar2 5/48^M
> SisteConfig.txt
tester port print!!!!

Answer 1

The input file ("rport.txt") probably contains a newline. Strip whitespace from the end of the read input, and it should be ok.

Answer 2

The file probably ends with an end-of-line sequence.
Sleazy, brittle solution:
fread(port, 1,size-1, file); // If it's just a CR or LF
fread(port, 1,size-2, file); // If it's a combination of CRLF.
// your code continues here
A better, portable solution will do something like this:
char *port = calloc(size+1, sizeof(char)); // Ensure string will end with null
int len = fread(port, 1, size, file); // Read len characters
char *end = port + len - 1; // Last char from the file
// If the last char is a CR or LF, shorten the string.
while (end >= p) && ((*end == '\r') || (*end == '\n')) {
*(end--) = '\0';
}
Here's working code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
char getConfig[100] = "/home/glennwiz/develop/c/SnuPort/ExpGetConfig.sh ";
const char *filedumpto = " > lastConfig.txt";
int main(char argc, char *argv[]) {
FILE *file = fopen("rport.txt", "r");
if (file == NULL) {
return 1;
}
fseek(file, 0, SEEK_END);
long int size = ftell(file);
rewind(file);
char *port = calloc(size+1, 1);
int len = fread(port, 1, size, file); // Read len characters
char *end = port + len - 1; // Last char from the file
// While the last char is a CR or LF, shorten the string.
while ((end >= port) && ((*end == '\r') || (*end == '\n'))) {
*(end--) = '\0';
}
strcat(getConfig, argv[1]);
strcat(getConfig, port);
strcat(getConfig, filedumpto);
printf("%s\n", getConfig);
return 0;
}