i wanted to use system() defined in process.h to fiddle with folders and stuff using my C program. but system() never succeeds ..it returns -1. this is my code and my output. Code: #include<stdio.h> #include<conio.h> #include<dos.h> #include<string.h> void main(int argc,char *argv[],char *env[]) { int i=0; char *ptr,*ptrnew; clrscr(); /*ptr=getenv("PATH"); strcpy(ptrnew,"PATH="); strcat(ptrnew,ptr); strcat(ptrnew,";C:\\TC\\TC\\BIN"); putenv(ptrnew); */ printf("%d\n\n",system("dir")); for(;env[i]!=NULL;i++) printf("%s\n",env[i]); } OUTPUT: -1 COMSPEC=C:\WINDOWS\SYSTEM32\COMMAND.COM ALLUSERSPROFILE=C:\DOCUME~1\ALLUSE~1 APPDATA=C:\DOCUME~1\HARIHA~1\APPLIC~1 CLASSPATH=.;C:\Program Files\QuickTime\QTSystem\QTJava.zip CLIENTNAME=Console COMMONPROGRAMFILES=C:\PROGRA~1\COMMON~1 COMPUTERNAME=SRIRAAMX-3F75EB FP_NO_HOST_CHECK=NO HOMEDRIVE=C: HOMEPATH=\Documents and Settings\hariharan LOGONSERVER=\\SRIRAAMX-3F75EB NUMBER_OF_PROCESSORS=1 OS=Windows_NT PATH=C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\PROGRA~1\QUICKT~ 1\QTSystem\;C:\TC\TC\BIN PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH PROCESSOR_ARCHITECTURE=x86 PROCESSOR_IDENTIFIER=x86 Family 15 Model 3 Stepping 3, GenuineIntel PROCESSOR_LEVEL=15 PROCESSOR_REVISION=0303 PROGRAMFILES=C:\PROGRA~1 PROMPT=$P$G QTJAVA=C:\Program Files\QuickTime\QTSystem\QTJava.zip SESSIONNAME=Console SYSTEMDRIVE=C: SYSTEMROOT=C:\WINDOWS TEMP=C:\WINDOWS\TEMP TMP=C:\WINDOWS\TEMP USERDOMAIN=SRIRAAMX-3F75EB USERNAME=hariharan USERPROFILE=C:\DOCUME~1\HARIHA~1 __COMPAT_LAYER=EnableNXShowUI BLASTER=A220 I5 D1 P330 T3 .................................................................................................................................. the comment part was also used to include the environment variable at runtime. but no fruits even then. the directory of my tc.exe is C\TC\TC\BIN as u can see its included in the environment pointer list. pls help me out. peace!
Read this with regard to putting code tags around your code. Then I'll have a look. It's too ugly, now.
I have done that for you as of now but you should be doing that yourself. Read the content in the link by DaWei
You do not understand pointers. You have declared a pointer, but a pointer must point at a valid storage area. To be useful, it is part of a pair: the pointer, and where the pointer points. You have not provided the latter part. Read this and think about it. Read it two or three times, if necessary.
u dont seem to understand my problem sir.pls read my question properly. i know a lot more about pointers than u seem to think. my compiler seems to allocate memory .(its is not evident from the output) but its on comment anyway. but as u can see ,path value in output lists c:/tc/tc/bin i added it from mycomputer.
