http://krischer.org/ 2010-09-09T00:00:35+02:00 http://krischer.org/ http://krischer.org/lib/images/favicon.ico text/html 2009-01-14T23:48:52+02:00 http://krischer.org/code/ansi_c/snipplets/read_textfiles_linewise Das folgende kurze Programm zeigt die wesentlichen Funktionen, die zum Lesen aus einer Datei benötigt werden: /* Zugriff auf eine Datei 20.5.97/Pe */ #include <stdio.h> char datnam[40] = "daten.txt"; /* nur global moeglich !! */ int main( void ) { FILE * datei; /* Struktur fuer Datei */ char zeile[80]; /* Annahme: max 80 Zeichen */ datei = fopen( datnam, "r" ); /* r = read */ if( datei == 0 ) { … text/html 2009-01-14T23:48:51+02:00 http://krischer.org/code/ansi_c/snipplets/reading_a_single_character define this function for cutting every following ‚\n‘ #include <stdio.h> void drain_stdin (void) { int c; do { c = fgetc(stdin); } while (c != EOF && c != '\n'); } example use with scanf() for a char. now the while-loop isn’t executed twice while ENTERing a character. text/html 2009-01-14T23:48:50+02:00 http://krischer.org/code/ansi_c/snipplets/sorting_structs Function to Sort a struct-array called „adres“ after namewise, with holding additional fields together void Sort(struct adres sort[], int nr) { int i,j; struct adres *temp; temp = (struct adres *)malloc(sizeof(struct adres *)); if(NULL == temp) { printf("Konnte keinen Speicher reservieren...\n"); return; } for(i = 0; i < nr; i++) { for(j=i+1;j<nr;j++) { if(strcmp(sort[i].nname, sort[j].nname) > 0) { /*could be a "a < i" operation for numberwise sort… text/html 2009-01-14T23:48:51+02:00 http://krischer.org/code/ansi_c/snipplets/start Some working examples of stuff often or sometimes or ever used text/html 2009-01-14T23:48:52+02:00 http://krischer.org/code/ansi_c/snipplets/user_details /* Program to get the Details of the user like User's Real Name, Username and Shell */ #include <pwd.h> /* getpwdid */ #include <sys/types.h> #include <unistd.h> #include <stdio.h> void user_details(void); int main(void) { user_details(); return 0; } void user_details(void) { struct passwd *passwd; /* man getpwuid */ passwd = getpwuid ( getuid()); /* Get the uid of the running processand use it to get a record from /etc/passwd */ printf("\n The Real U…