1) There is a problem in getfloats() function. cc[0] is assigned several times
but cc[1] is never. In C/C++, local variable is not initialized unless you
explicitly initialize.
char cc1[2]; // global variable. Always initialized is '\0\0'
void f() {
char cc2[2]; // local variable. Not initialized. Unknown value
cc2[0]='a'; // cc2 is 'a' + unknown value
}
You were just lucky that cc happend to be initialized to '\0\0'. It can
cause problem in any compiler and any environment.
2) Another point that might cause problem is fgets. I think it is safer to
replace '\n' at the end of fgets read string to 0.
fgets(tmpstr,SLEN,infp);
char *p=strchr(tmpstr,'\n');
if(p) *p = 0;
Masaharu Goto
----------------------------------------------------------------------
The following code crashes most of the time with the
segmentation violation in root 2.20/06 for SunOS5.4 on Sparc.
But when compiled with gcc it works fine. It works also
when instead calling a function I parse a string inside
main macro.
Thanks for any hints.
Regards
Michal Lijowski
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
// -------------------------------------------------------------------------
int getfloats(char *tmpstr, float *aa)
// extracts up to 10 floating point numbers from a string
{
int SLEN = 40;
char cc[2], str1[SLEN];
int sl = strlen(tmpstr);
printf("%4d %s", sl, tmpstr);
cc[0] = tmpstr[0];
int jj = 0;
int ii = 0;
while ( (ii < 10) && (jj < sl) ) {
str1[0] = '\0';
while ( (cc[0] != ' ') && (jj < sl) ) {
strncat(str1, cc, 1);
jj++;
cc[0] = tmpstr[jj];
}
aa[ii] = atof(str1);
ii++;
// skip white spaces
while ( (cc[0] == ' ') && (jj < sl) ) {
jj++;
cc[0] = tmpstr[jj];
}
}
return ii;
}
// ---------------------------------------------------------------------
void test_read()
{
char infile[200];
float aa[10];
int SLEN = 80, nn;
char tmpstr[SLEN], str1[20], cc[2];
sprintf(infile, "tmp.dat");
printf("%s\n", infile);
FILE *infp = fopen(infile, "r");
if (infp == NULL) {
printf("test_read2b can't open %s\n", infile);
exit(1);
}
int npts = 0;
// loop until EOF
while (fgets(tmpstr, SLEN, infp) != NULL) {
printf(" %s", tmpstr);
nn = getfloats(tmpstr, aa);
for (int ii = 0; ii < nn; ii++) {
printf(" %f ", aa[ii]);
}
printf("\n");
npts++;
}
fclose(infp);
}