fgetenv.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 77 行

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*
*                            Open Watcom Project
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*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
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*    This file contains Original Code and/or Modifications of Original
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//
// FGETENV      : get value of environment variable
//

#include "ftnstd.h"

#include <stddef.h>
#include <malloc.h>
#include <string.h>
#include <process.h>
#include <pgmacc.h>


intstar4        fortran FGETENV( string PGM *env_var, string PGM *value ) {
//=========================================================================

    char        *buff;
    char        *ptr;
    int         len;

    len = 0;
    for(;;) {
        if( len == env_var->len ) break;
        if( env_var->strptr[ len ] == ' ' ) break;
        ++len;
    }
    if( len == 0 ) return( 0 );
    buff = alloca( len + sizeof( char ) );
    if( buff != NULL ) {
        pgm_memget( buff, env_var->strptr, len );
        buff[ len ] = NULLCHAR;
        ptr = getenv( buff );
        if( ptr != NULL ) {
            len = strlen( ptr );
            if( len > value->len ) {
                len = value->len;
            }
            pgm_memput( value->strptr, ptr, len );
            pgm_memset( value->strptr + len, ' ', value->len - len );
            return( len );
        }
    }
    return( 0 );
}